KS3 Algebra Basics

KS3 Algebra Basics

​Algebra rules

• ​We don't write a multiplication sign, 2a means 2 x a

• ​We don't write the number 1, a means 1a

• Please write these examples down!

Multiple Choice

Simplify 8a + 3a

• 11a

• a

• 5a

• $$a^{11}$$

Multiple Choice

Simplify the following expression :

• 5a+10b

• 6a+8b

• 6a+10b

• 5a+9b

Multiple Choice

Simplify the following expression :

• 8x-6

• 8x+6

• 7x+6

• 8x+5

Multiple Choice

$$a^2\ +\ a^2\$$  

• $$a^4$$  

• $$4a$$  

• 4 $$a^2$$  

• $$2a^2$$  

Multiple Choice

Simplify by combining like terms:

$$7b-3b+4f$$  

• $$10b+4f$$  

• $$8b$$  

• $$4b-4f$$

• $$4b+4f$$   

Multiple Choice

Simplify by combining like terms:

$$4t-t+3$$  

• $$4t-4$$  

• $$5t+3$$  

• $$3t+3$$  

• $$5t-3$$  

Multiple Choice

Solve for b.

9b=18

• 9

• 2

• 27

• -11

Solve y +14=20

• The inverse operation of addition is subtraction.

• Subtract 14 from both sides of the equal sign

• 20-14=6

• y=6

Solve x -120 = 80

• The inverse operation of subtraction is addition

• Add 120 to both sides of the equal sign.

• 80 +120= 200

• x=200

Solve 3n=12

• The inverse operation of multiplication is division

• Divide both sides by 3

• 12/3=4

• n=4

• The inverse operation of division  is multiplication 

• Multiply both sides by 2

• 16(2)=32

• k=32

Multiple Choice

Solve for x:

• x = 20
• x = 7
• x = 10
• x = 3

Multiple Choice

Solve the equation
3x = 27. 

• x = 24
• x = 81
• x = 9

Multiple Choice

Find the value of a: $$12\ =\ \frac{a}{4}$$  

• 48

• 3

• 8

Multiple Choice

$$21\ =\ 14\ +\ x$$  

• x = 7

• x = 35

• x = 294

• x = 1.5

Multiple Choice

Find the value of m

: m + 4 = 12

• 16

• 8

• 48

• 3

​Substitution means replace

• ​So when we are given the value of a number, we can replace it in the question.

​

• ​Copy down the example :)

​

• ​There is a video to help on the next slide if you want to watch it

Multiple Choice

If $$c=5$$ , find  $$2c$$  

• 7

• 8

• 9

• 10

Multiple Choice

If $$d=11$$ , find  $$d+3$$  

• 11

• 12

• 13

• 14

Multiple Choice

If $$b=10$$ , find  $$\frac{40}{b}$$  .

• 10

• 2

• 30

• 4

Multiple Choice

If a = 4 and b = 6, what is the value of 3a + 5b?

• 40
• 42
• 44
• 46

Multiple Choice

If x = 5, find the value of 7x-1.

• 34
• 36
• 35
• 37

Multiple Choice

If $$e=8$$ , find  $$e+e$$  

• 16

• 88

• 14

• 0

Multiple Choice

If  $$g=-9$$ , find  $$g+11$$  

• $$2$$  

• $$-2$$  

• $$20$$  

• $$-20$$  

Multiple Choice

If  $$h=7$$  , find  $$h^2$$  

• 14

• 49

• 72

• 36