Question

Choose the answer based on the most efficient method as presented in the lesson.

If the first step in the solution of the equation -9 + x = 5x - 7 is "subtract x," then what should the next step be?

subtract 5x

add 7

add 9

Answer 1

The next one is add 7 since after you subtract x you would have -9 = 4x - 7

Answer 2

Option 2 - Add 7

Explanation:

Given : If the first step in the solution of the equation -9 + x = 5x - 7 is "subtract x,"

To find : What should the next step be?

Solution :

Expression
`-9 + x = 5x - 7`

Step 1 - Subtract x from both side,

`-9 + x-x= 5x - 7-x`

`-9= 4x - 7`

Step 2 - Add 7 both side,

`-9+7= 4x - 7+7`

`-2= 4x`

Step 3 - Solve,

`x=(-2)/(4)`

`x=-(1)/(2)`

So, The best next step is ''add 7 both side''

Therefore, Option 2 is correct.