Question

Which expression is equivalent to 20 — 3(x + 2)?A 3X+ 14B —3x + 14 C -9x + 21 D 17x— 34

Answer 1

first option

Explanation:

`((-2)/(x)+(5)/(y) )/((3)/(y)-(2)/(x) )` ← combine fractions on numerator and denominator

=
`((-2y+5x)/(xy) )/((3x-2y)/(xy) )`

leave numerator, change division to multiplication and turn denominator 'upside down'

=
`(-2y+5x)/(xy)` ×
`(xy)/(3x-2y)` ← cancel xy on numerator/ denominator

=
`(-2y+5x)/(1)` ×
`(1)/(3x-2y)`

=
`(-2y+5x)/(3x-2y)`

Answer 2

We have to simplify the expression:

`20-3(x+2)`

and see which expression is equivalent.

We can do it like this:

`\begin{gathered} 20-3(x+2) \\ 20-3\cdot x-3\cdot2 \\ 20-3x-6 \\ 20-6-3x \\ 14-3x \\ -3x+14 \end{gathered}`

This expression is equivalent to -3x+14.

Answer: -3x+14 [Option B]