SOLUTION: The absolute value of the sum of -7 and twice a number is 23 . find the number

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Question 1093819: The absolute value of the sum of -7 and twice a number is 23 . find the number
Found 3 solutions by josgarithmetic, ikleyn, MathTherapy:
Answer by josgarithmetic(39631) About Me  (Show Source):
You can put this solution on YOUR website!
"...sum of -7 and twice a number..."

abs%28-7%2B2x%29=23
-
Either 2x-7=23 or 2x-7=-23;
Solve for each case.








Incorrect interpretation-------------------------------
abs%28-7-%282x%29%29=23
abs%282x%2B7%29=23
.
.
system%28x=cross%28-15%29%2COR%2Cx=cross%288%29%29

Answer by ikleyn(52927) About Me  (Show Source):
You can put this solution on YOUR website!
.
The absolute value of the sum of -7 and twice a number is 23 . find the number
~~~~~~~~~~~~~~~~~~~~~~~~ 

The Math translation of the condition is this equation

|-7 +2x| = 23.     // Notice it is DIFFERENT from that of @josgarithmetic, which is   W R O N G.


EITHER

a)  -7 + 2x = 23  ====>  2x = 23+7 = 30  ====>  x = 15,


OR


b)  -7 + 2x = -23  ====>  2x = -23 + 7 = -16  ====>  x = -8.


Answer.  The original equation has two solutions:  x = 15  and/or  x = -8.

Be aware: the solution and the answer by @josgarithmetic both are W R O N G.


Simply ignore it . . .



Answer by MathTherapy(10558) About Me  (Show Source):
You can put this solution on YOUR website!

The absolute value of the sum of -7 and twice a number is 23 . find the number
Why does this dude continue to provide wrong answers to these people?

Correct answer: highlight_green%28matrix%281%2C3%2C+%2215%2C%22%2C+or%2C+-+8%29%29