9G (2.2) Equations

Equations

​(2.2)

An equation is when you have two expressions with an equal sign between them.


You probably already knew that.

Multiple Choice

$$5\ +\ 9=14$$

• That's an equation because there's an = sign

• That's just an expression

• That's not an expression or an equation

Multiple Choice

$$5\ +\ 9$$

• That's an equation because there's an = sign

• That's just an expression

• That's not an expression or an equation

Multiple Choice

$$9-9$$

• That's an equation because there's an = sign

• That's just an expression

• That's not an expression or an equation

Multiple Choice

$$9-9=0$$

• That's an equation because there's an = sign

• That's just an expression

• That's not an expression or an equation

Multiple Choice

$$0+0=0$$

• That's an equation because there's an = sign

• That's just an expression

• That's not an expression or an equation

Multiple Choice

$$0\cdot1$$

• That's an equation because there's an = sign

• That's just an expression

• That's not an expression or an equation

Multiple Choice

$$0\cdot1=0$$

• That's an equation because there's an = sign

• That's just an expression

• That's not an expression or an equation

Multiple Choice

$$\frac{1}{0}$$

• That's an equation because there's an = sign

• That's just an expression

• That's not an expression or an equation

Multiple Choice

$$\frac{1}{0}=\infty$$

• That's an equation because there's an = sign

• That's just an expression

• That's not an expression or an equation

Multiple Choice

$$x+7$$

• That's an equation because there's an = sign

• That's just an expression

• That's not an expression or an equation

Multiple Choice

$$x+7=11$$

• That's an equation because there's an = sign

• That's just an expression

• That's not an expression or an equation

Multiple Choice

$$x-7=11$$

• That's an equation because there's an = sign

• That's just an expression

• That's not an expression or an equation

Multiple Choice

$$x-7=15$$

• That's an equation because there's an = sign

• That's just an expression

• That's not an expression or an equation

Multiple Choice

$$x-7=40$$

• That's an equation because there's an = sign

• That's just an expression

• That's not an expression or an equation

Multiple Choice

$$x-7=127$$

• That's an equation because there's an = sign

• That's just an expression

• That's not an expression or an equation

Multiple Choice

$$x-7=1204$$

• That's an equation because there's an = sign

• That's just an expression

• That's not an expression or an equation

Multiple Choice

$$x\ -7=670,328,492$$

• That's an equation because there's an = sign

• That's just an expression

• That's not an expression or an equation

Multiple Choice

We have the expression:

$$x+9$$ ,

Can you figure out what the value of the expression is?

• x = 20

• x = 11

• x = 9

• x = -9

• No, not until there's an equal sign

Multiple Choice

Now we have the equation:

$$x+9=19$$ ,

Can you figure out what the value of x is?

• x = 10

• x = 9

• x = 19

• x = 11

• No, not until we say what x is.

Multiple Choice

We have the expression:

$$4+x$$ ,

Can you figure out what the value of the expression is?

• x = 10

• x = 8

• x = 4

• x = -4

• No, not until there's an equal sign

Multiple Choice

Now we have the equation:

$$4+x=24$$ ,

Can you figure out what the value of x is?

• x = 20

• x = 19

• x = 21

• x = 24

• No, not until we say what x is.

Multiple Choice

We have the expression:

$$x+1$$ ,

Can you figure out what the value of the expression is?

• x = 10

• x = 8

• x = 4

• x = -4

• No, not until there's an equal sign

Multiple Choice

Now we have the equation:

$$x+1=30$$ ,

Can you figure out what the value of x is?

• x = 28

• x = 29

• x = 31

• x = 30

• No, not until we say what x is.

Multiple Choice

We have the expression:

$$x-5$$ ,

Can you figure out what the value of the expression is?

• 10

• 8

• 4

• -4

• No, not until there's an equal sign

Multiple Choice

Now we have the equation:

$$x-5=15$$ ,

Can you figure out what the value of x is?

• x = 15

• x = 21

• x = 20

• x = 25

• No, not until we say what x is.

Multiple Choice

We have the expression:

$$x-9$$ ,

Can you figure out what the value of the expression is?

• 19

• 9

• -9

• 0

• No, not until there's an equal sign

Multiple Choice

Now we have the equation:

$$x-9=1$$ ,

Can you figure out what the value of x is?

• x = 15

• x = 10

• x = 9

• x = 11

• No, not until we say what x is.

Multiple Choice

We have the expression:

$$x-11$$ ,

Can you figure out what the value of the expression is?

• 19

• 9

• -9

• 0

• No, not until there's an equal sign

Multiple Choice

Now we have the equation:

$$x-11=0$$ ,

Can you figure out what the value of x is?

• x = 12

• x = 10

• x = 0

• x = 11

• No, not until we say what x is.

Multiple Choice

We have the expression:

$$x\times3$$ ,

Can you figure out what the value of the expression is?

• 3

• 13

• 0

• -3

• No, not until there's an equal sign

Multiple Choice

Now we have the equation:

$$x\times3=9$$ ,

Can you figure out what the value of x is?

• x = 3

• x = 4

• x = 0

• x = 9

• No, not until we say what x is.

Multiple Choice

We have the expression:

$$5\cdot x$$ ,

Can you figure out what the value of the expression is?

• 5

• 10

• 0

• $$\frac{1}{5}$$

• No, not until there's an equal sign

Multiple Choice

Now we have the equation:

$$5\cdot x=10$$ ,

Can you figure out what the value of x is?

• x = 2

• x = 4

• x = $$\frac{1}{2}$$

• x = 3

• No, not until we say what x is.

Multiple Choice

Now we have the equation:

$$4\left(x\right)=16$$ ,

Can you figure out what the value of x is?

• x = 2

• x = 4

• x = $$5$$

• x = 3

• No, not until we say what x is.

Multiple Choice

We have the expression:

$$x\div3$$ ,

Can you figure out what the value of the expression is?

• 3

• 9

• 0

• $$\frac{1}{3}$$

• No, not until there's an equal sign

Multiple Choice

Now we have the equation:

$$x\div3=3$$ ,

Can you figure out what the value of x is?

• x = 6

• x = 3

• x = $$9$$

• x = 1

• No, not until we say what x is.

Multiple Choice

We have the expression:

$$\frac{x}{2}$$ ,

Can you figure out what the value of the expression is?

• 2

• 4

• 0

• $$\frac{1}{2}$$

• No, not until there's an equal sign

Multiple Choice

Now we have the equation:

$$\frac{x}{2}=10$$ ,

Can you figure out what the value of x is?

• x = 20

• x = 2

• x = $$5$$

• x = 15

• No, not until we say what x is.

Multiple Choice

We have the expression:

$$\frac{x}{5}$$ ,

Can you figure out what the value of the expression is?

• 5

• 4

• 0

• $$\frac{1}{5}$$

• No, not until there's an equal sign

Multiple Choice

Now we have the equation:

$$\frac{x}{5}=20$$ ,

Can you figure out what the value of x is?

• x = 100

• x = 20

• x = $$40$$

• x = 50

• No, not until we say what x is.

Multiple Choice

We have the expression:

$$7\left(x\right)$$ ,

Can you figure out what the value of the expression is?

• 7

• 4

• 0

• $$\frac{1}{7}$$

• No, not until there's an equal sign

Multiple Choice

Now we have the equation:

$$7\left(x\right)=21$$ ,

Can you figure out what the value of x is?

• x = 3

• x = 4

• x = $$5$$

• x = 21

• No, not until we say what x is.

Multiple Choice

We have the expression:

$$x-6$$ ,

Can you figure out what the value of the expression is?

• 7

• 6

• 0

• $$-6$$

• No, not until there's an equal sign

Multiple Choice

Now we have the equation:

$$x\ -\ 6\ =\ 44$$ ,

Can you figure out what the value of x is?

• x = 50

• x = 25

• x = $$34$$

• x = 38

• No, not until we say what x is.

Multiple Choice

Now we have the equation:

$$x\ -\ 7\ =\ 43$$ ,

NOW ADD 7 TO BOTH SIDES OF THE EQUATION

Can you figure out what the value of x is?

• x = 50

• x = 25

• x = $$34$$

• x = 35

• No, not until we say what x is.

Multiple Choice

Now we have the equation:

$$x\ -\ 7\ =\ 10$$ ,

NOW ADD 7 TO BOTH SIDES OF THE EQUATION

Can you figure out what the value of x is?

• x = 17

• x = 20

• x = 3

• x = 16

• No, not until we say what x is.

Multiple Choice

Now we have the equation:

$$x\ -\ 7\ =\ 12$$ ,

NOW ADD 7 TO BOTH SIDES OF THE EQUATION

Can you figure out what the value of x is

• x = 19

• x = 20

• x = 18

• x = 5

• No, not until we say what x is.

Multiple Choice

Now we have the equation:

$$x\ -\ 7\ =\ 5$$ ,

NOW ADD 7 TO BOTH SIDES OF THE EQUATION

Can you figure out what the value of x is

• x = 12

• x = 13

• x = 11

• x = -2

• No, not until we say what x is.

Multiple Choice

Now we have the equation:

$$x\ +4\ =\ 18$$ ,

NOW SUBTRACT 4 FROM BOTH SIDES OF THE EQUATION

Can you figure out what the value of x is

• x = 14

• x = 13

• x = 11

• x = 22

• No, not until we say what x is.

Multiple Choice

Now we have the equation:

$$x\ +9\ =38\$$ ,

NOW SUBTRACT 9 FROM BOTH SIDES OF THE EQUATION

Can you figure out what the value of x is

• x = 29

• x = 30

• x = 31

• x = 32

• No, not until we say what x is.

Multiple Choice

Now we have the equation:

$$2\left(x\right)\ \ =32\$$ ,

NOW DIVIDE BOTH SIDES OF THE EQUATION BY 2

Can you figure out what the value of x is

• x = 16

• x = 17

• x = 30

• x = 64

• No, not until we say what x is.

Multiple Choice

Now we have the equation:

$$5\left(x\right)\ \ =40$$ ,

NOW DIVIDE BOTH SIDES OF THE EQUATION BY 5

Can you figure out what the value of x is

• x = 8

• x = 45

• x = 35

• x = 7

• No, not until we say what x is.

Multiple Choice

Now we have the equation:

$$7\left(x\right)\ \ =42$$ ,

NOW DIVIDE BOTH SIDES OF THE EQUATION BY 7

Can you figure out what the value of x is

• x = 6

• x = 5

• x = 35

• x = 49

• No, not until we say what x is.

Multiple Choice

Now we have the equation:

$$6\left(x\right)\ \ =72$$ ,

NOW DIVIDE BOTH SIDES OF THE EQUATION BY 6

Can you figure out what the value of x is

• x = 12

• x = 7

• x = 15

• x = 78

• No, not until we say what x is.

Multiple Choice

Now we have the equation:

$$\frac{x}{4}\ \ =20$$ ,

NOW MULTIPLY BOTH SIDES OF THE EQUATION BY 4

Can you figure out what the value of x is

• x = 80

• x = 5

• x = 10

• x = 6

• No, not until we say what x is.

Multiple Choice

Now we have the equation:

$$\frac{x}{7}\ \ =8$$ ,

NOW MULTIPLY BOTH SIDES OF THE EQUATION BY 7

Can you figure out what the value of x is

• x = 56

• x = 49

• x = 15

• x = 1.14

• No, not until we say what x is.

Multiple Choice

Now we have the equation:

$$\frac{x}{3}\ \ =21$$ ,

NOW MULTIPLY BOTH SIDES OF THE EQUATION BY 3

Can you figure out what the value of x is

• x = 63

• x = 60

• x = 7

• x = 24

• No, not until we say what x is.

Multiple Choice

Now we have the equation:

$$\frac{x}{5}\ \ =25$$ ,

NOW MULTIPLY BOTH SIDES OF THE EQUATION BY 5

Can you figure out what the value of x is

• x = 125

• x = 100

• x = 20

• x = 5

• No, not until we say what x is.

Multiple Choice

Now we have the equation:

$$\frac{x}{9}\ \ =6$$ ,

NOW MULTIPLY BOTH SIDES OF THE EQUATION BY 6

Can you figure out what the value of x is

• x = 54

• x = 63

• x = -3

• x = 0.666

• No, not until we say what x is.

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