Algebra: Substitution

Work out the value of the expression when x = 3, y = – 2 and z = – 4.
2x² + z²   

• 2

• 27

• 50

• 34

If y=7,find the value of 2(y+4)

• 11

• 22

• 20

• 18

If y=4,find the value of 3y+5

• 27

• 12

• 17

If a=6 and b= 7,find the value of 15-a-b

• 2

• 3

• 4

If a=4,b=5 and c=6,find 2c-a-b

• 4

• 3

• 6

When x = 3, y = 6 and z = 7, find 2x - z

• -1

• -2

• -3

• -4

Work out the value of the following expressions when a = 3, b = 4 and c = 5.
2a

• 5

• 6

• 8

• 10

If a = 4 & b = 6, what is 3a + 5b?

• 40

• 42

• 44

• 46

If p=3 and q=5,find 
p +q+2

• 12

• 10

• 8

If a = 4 & b = 6, what is 3a + 5b?

• 40

• 42

• 44

• 46