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1 vote
What's X? to:
15x - 7x = (-52) - 5x

2 Answers

7 votes
First, condense what's on the right side of the problem:

15x-7x=-52-5x \\ 8x=-52-5x
Nest, get all the terms with x on one side. To do this, add 5x to both sides:

(8x)+5x=(-52-5x)+5x \\ 13x=-52
Finally, divide each side by 13 to get x alone:

(13x)/13=(-52)/13 \\ x=-4
The answer is x = -4.

To check, simply plug -4 in for x like so:

15(-4)-7(-4)=-52-5(-4) \\ -60--28=-52--20 \\ -60+28=-52+20 \\ -32=-32
Since we get the same answer on both sides of the equation, we know our answer is correct!

Hope this helps!
User Anoop Mishra
by
8.4k points
6 votes
-4

Because 15x-7x= 8x
8x+5x= 13x
13x= -52
-52 / 13= -4
x = -4

User Manish Parmar
by
8.3k points