Question

Sharon tried to solve an equation step by step.

\qquad\begin{aligned} 9&=-3(e-2)\\\\ \\ 9&=-3e+6&\green{\text{Step } 1}\\\\ \\ 15&=3e&\blue{\text{Step } 2}\\\\ \\ 5&=e&\purple{\text{Step } 3}\\\\ \end{aligned}

9

9

15

5

​


=−3(e−2)

=−3e+6

=3e

=e

​


Step 1

Step 2

Step 3

​


Find Sharon's mistake.

Answer 1

Step 2

Explanation:

Khan academy inequalities 7th grade math unit test

Answer 2

Sharon made a mistake in step 2.

Explanation:

Sharon tried to solve an equation step by step.

`\qquad\begin{aligned} 9&=-3(e-2)\\\\ \\ 9&=-3e+6&\green{\text{Step } 1}\\\\ \\ 15&=3e&\blue{\text{Step } 2}\\\\ \\ 5&=e&\purple{\text{Step } 3}\\\\ \end{aligned}`

The correct steps are:

The given equation is

`9=-3(e-2)`

Step 1: Using distributive property we get

`9=-3e-3(-2)`

`9=-3e+6`

Step 2: Subtract 6 from both sides.

`9-6=-3e+6-6`

`3=-3e`

Step 3: Divide both sides by -3.

`(3)/(-3)=(-3e)/(-3)`

`-1=e`

Therefore, Sharon made a mistake in step 2.