Question

#13-8: Write an equivalent expression for 3(3a-2)+4-a and simplify it. Evaluate the expression if a=-2.

Answer 1

-18

Explanation:

3(3a - 2) + 4 - a

Simplified becomes;

9a - 6 + 4 - a

= 9a - a - 6 + 4

= 8a - 2

If a = -2 then;

8a - 2 = -16 - 2 = -18

Answer 2

`\huge{\boxed{8a-2}}\ \ \huge{\boxed{-18}}`

Distribute the
`3` to the
`(3a-2)`.
`9a-6+4-a`

Move the common terms next to each other.
`9a-a-6+4`

Combine the variables.
`8a-6+4`

Combine the constants.
`\boxed{8a-2}`

Substitute in the variable.
`8(-2)-2`

Multiply.
`-16-2`

Subtract.
`\boxed{-18}`