SOLUTION: i want to start by saying thanks for helping me....but i'm juz solving a regular equation and it's -2x-7=9....and the answer is -8 but i thought it should be -1. because when i sub

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Question 153842This question is from textbook algebra 2
: i want to start by saying thanks for helping me....but i'm juz solving a regular equation and it's -2x-7=9....and the answer is -8 but i thought it should be -1. because when i subtract the -7 from 9 it makes 2...but obviously the book added the 7 and 9....but there not both positive. So, can you please explain that to me? thanks This question is from textbook algebra 2

Found 2 solutions by nerdybill, hitchick247:
Answer by nerdybill(7384) (Show Source):
You can put this solution on YOUR website!
If you started with:
-2x-7=9
.
The idea is to "isolate" the unknown (x) to one side of the equation -- doesn't matter which side.
.
-2x-7=9
We begin by adding 7 to both sides:
-2x-7+7 = 9+7
Simplifying we get:
-2x = 16
Finally, we divide both sides by -2:
(-2x)/(-2) = 16/(-2)
Notice on the left side the -2 cancels leaving:
x = 16/(-2)
Finally, on the right we divide 16 by a -2:
x = -8

Answer by hitchick247(3) (Show Source):
You can put this solution on YOUR website!
you at 7 to the 9 making it 16 then your problem becomes -2x=16
then divide -2 from the 16 getting the x alone equaling -8
answer: x= -8