How do you solve |7+ 7r | + 5= 40?

2 Answers
Mar 26, 2018

Answer: r = -6, 4

Explanation:

abs(7 + 7r) + 5 = 40

abs(7 + 7r) = 35

7 + 7r = +- 35

7 + 7r = + 35 => r = 28/7 = 4

7 + 7r = - 35 => r = -42/7 = -6

Mar 26, 2018

r=-6" or "r=4

Explanation:

"subtract 5 from both sides"

rArr|7+7r|=35

"the expression inside the absolute value can be positive"
"or negative"

color(magenta)"Positive expression"

rArr7+7r=35larrcolor(blue)"subtract 7 from both sides"

rArr7r=28larrcolor(blue)"divide both sides by 7"

rArrr=4

color(magenta)"Negative expression"

-7-7r=35larrcolor(blue)"add 7 to both sides"

rArr-7r=42larrcolor(blue)"divide both sides by "-7

rArrr=-6

color(blue)"As a check"

r=4rArr|35|+5=35+5=40color(white)(x)✔︎

r=-6rArr|-35|+5=35+5=40color(white)(x)✔︎

rArrx=-6" or "x=4" are the solutions"