TTPA Lessons 50-51

​Lessons 50-51

By Sarah Monda

Expression or Equation?

​What's the difference?

An expression is a combination of numbers and variables WITHOUT an equals sign.

An equation is 2 expressions that are equal to each other.

You can simplify an expression, but only equations can be solved.

Multiple Choice

x + 15

• expression

• equation

Multiple Choice

b + 3 = 19

• expression

• equation

Multiple Choice

9 ÷ h

• expression

• equation

Multiple Choice

15y = 45

• expression

• equation

Multiple Choice

15 = d – 36

• expression

• equation

Solving linear equations

1. Simplify the expressions where possible (PEMDAS).

2. Combine like terms where possible.

3. Isolate the variable on one side of the equation by using inverse operations.

Math Response

$$44=10+2x-6$$

Type answer here

Correct Answer: 20

Deg^°

Rad

Parentheses in equations

​2(x-5)=8

In this example, we cannot simplify the parentheses because we don't know x. What we need to do first is DISTRIBUTE the coefficient of 2 across both x and -5.

2x-10=8

Now we can solve for x.

​Another example

​Again, there is no way to combine terms. So first we distribute the 0.5 coefficient across the 6 and -x.

Then we can subtract or add to move like terms to one side of the equation.

Finally, we divide to solve for x.

Your turn

4-6x+4=2(x-4)

Put your solution for x in the chat.

Math Response

$$3\left(x+2\right)=21$$

Type answer here

Correct Answer: 5

Deg^°

Rad

Fill in the Blank

Solve for y.

$$-9+7y+1=10+10y$$  

Check it

​Always check your answers

You can check your answers by substituting the solution for the variable back into the original equation. If the equation does not balance, you know you made a mistake.

Why is it important to identify our mistakes?

Multiple Choice

Which step contains an error?

• Step 1 (distributing)

• Step 2 (combining like terms)

• Step 3 (arithmetic)

• Step 4 (division)

• No Error

Multiple Choice

Which step contains an error?

• Step 1

• Step 2

• Step 3

• No Error

Multiple Choice

Which step contains an error?

• Step 1 (combining like terms)

• Step 2 (arithmetic)

• Step 3 (final division)

• No Error

Multiple Choice

$$\frac{\left(2x\ +\ 12\right)}{4}\ =\ 12$$  

• x = 48

• x = 18

• x = 20

• x = 50

Dropdown

To solve: 4x + 7 = 23

First you ​

Select answer

. Then you ​

Select answer

. This gives a solution of

Select answer

Fractions and variables

Sometimes you will have a fractional coefficient with a variable. In this case, remember that the variable ALWAYS goes with the numerator.

Math Response

Solve for x:

$$5+\frac{4}{3}x=17$$

Type answer here

Correct Answer: 9

Deg^°

Rad

Open Ended

What should be done first to solve for m?

$$\frac{2}{5}m+9=3$$

Home

Open in new tab

Copy link

Homework

Lessons 50-51

Remember to upload your gradebook screenshot on Canvas.

HAPPY THANKSGIVING! (no class next Monday)

Math lab every Monday in Google Meet 2:30-3:30