How do you solve 8abs(x+7)-3=5?

1 Answer
May 3, 2018

x=-8" or "x=-6

Explanation:

"the expression inside the absolute value bars can be"
"positive or negative hence we have to consider both"

"isolate "|x+7|" by adding 3 to both sides"

8|x+7|cancel(-3)cancel(+3)=5+3

rArr8|x+7|=8

"divide both sides by 8"

cancel(8)/cancel(8)|x+7|=8/8

rArr|x+7|=1

"consider the "color(magenta)" positive value ""of "x+7

rArrx+7=1larr"subtract 7 from both sides"

rArrx=1-7=-6

"consider the "color(magenta)"negative value ""of "x+7

rArr-(x+7)=1larr"distribute"

rArr-x-7=1larr"add 7 to both sides"

rArr-x=1+7=8

rArrx=-8

color(blue)"As a check"

Substitute these values into the left side of the equation and if equal to the right side then they are the solutions.

x=-6to8|-6+7|-3=8-3=5

x=-8to8|-8+7|-3=8|-1|-3=8-3=5

rArrx=-8" or "x=-6" are the solutions"