Evaluate Algebra Expression

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

• 5

• 6

• 8

• 10

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

• 10

• 12

• 15

• 36

Work out the value of the following expressions when a = 3, b = 4 and c = 5.
2a² + c²   

• 22

• 34

• 68

• 43

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

6a - 3d
when a = 1, d = 2

• 3

• 12

• 1

• 0

8y + 12 - 2z
for y = 4 and z = 2

• 40

• 20

• 84

• 34

Evaluate the expression

$$\left(6\times 6-9\right)-9÷3$$ 

• 9

• 24

• 18

• 6

What is the constant in the expression 2x+5

• 5

• 2x

• 2x and 5

• There is not a constant