Question

A student is asked to solve the equation 3c – 16 = 53 for c. Their work is shown. Original Problem 3c – 16 = 53 Step One +16 +16 Step Two 3c = 69 Step Three (3)3c = 69(3) Step Four c = 207 The student made a mistake in Step Three. What operation should the student have performed? Added 3 to both sides Multiplied by 69 on both sides Divided by 3 on both sides Subtracted 69 on both sides

Answer 1

Both sides should be divided by 3.

Explanation:

The student is given a common two-step equation to solve. In order to solve two-step equations you need to isolate the variable in order to find the value of that variable.


`3c-16=53`

`-16+16=0`

`53+16=69`

`3c=69`
In order to isolate the variable we must divide both sides by 3:

`3c/3=c`

`69/3=23`

`c = 23`

Therefore your answer is the third option or "both sides divided by 3."

I hope this helps.