Question

-7 + 4n = 9 Show your work!

Answer 1

Rewrite the equation in an easier way: 4n-7=9

Add 7 to both sides: 4n-7+7=9+7... 4n=16

Divide both sides by 4: 4n/4=16/4

ANSWER: N=4

Answer 2

First of all, add 7 to both sides, in order to cancel the -7:

$-7 + 4n +7= 9+7$

As we said, the -7 on the left hand side cancels out, while we can add it to the 9 on the right hand side:

$4n = 16$

Now, divide both sides by 4. As before, this is needed to cancel the four on the left hand side and isolate the x, while it is just a normal division between numbers on the right:

$\dfrac{4n}{4} = \dfrac{16}{4} \iff x = 4$