How do you solve #|- 4+ 5x | = 15#?

1 Answer
smendyka
Jan 6, 2017

See full solution process below in the Explanation

Explanation:

Because this equation contains an absolute value function we need to compute two different solutions.

Because the absolute value function takes and negative or positive term and converts it to a positive term we must solve the term within the absolute value for both the negative positive form of the equation.

Solution 1)

#-4 + 5x = -15#

#-4 + color(red)(4) + 5x = -15 + color(red)(4)#

#0 + 5x = -11#

#5x = -11#

#(5x)/color(red)(5) = (-11)/color(red)(5)#

#(color(red)(cancel(color(black)(5)))x)/cancel(color(red)(5)) = -11/color(red)(5)#

#x = -11/color(red)(5)# or #-2.2#

Solution 2)

#-4 + 5x = 15#

#-4 + color(red)(4) + 5x = 15 + color(red)(4)#

#0 + 5x = 19#

#5x = 19#

#(5x)/color(red)(5) = 19/color(red)(5)#

#(color(red)(cancel(color(black)(5)))x)/cancel(color(red)(5)) = 19/color(red)(5)#

#x = 19/color(red)(5)# or #3.8#

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