How do you solve #-10(x+5)+76= -12#?

2 Answers
Apr 19, 2016

Answer:

#x=3.8#

Explanation:

Multiplying out the brackets gives:

Don't forget you are multiplying by negative 10.

#-10x-50+76=-12#

#-10x+26=-12#

Subtract #color(blue)(26)# from both sides

#color(brown)(-10x+26color(blue)(-26)=-12color(blue)(-26))#

#-10x+0=-38#

Multiply both side by (-1) giving

#10x=38#

Divide both sides by 10

#10/10xx x= 38/10#

But #10/10 = 1#

#1xx x = 3.8#

#x=3.8#

'~~~~~~~~~ Check ~~~~~~~~~~~~~~~~
#color(brown)(-10(color(blue)(x)+5)+76=-12 -> -10(color(blue)(3.8)+5)+76=-12)#

Consider the left hand side only

#-38-50+76 -> -12#

#=> LHS=RHS" "-> x=3.8" confirmed"#

Apr 19, 2016

Answer:

RESULT: 3.8
Maybe this one will be a little bit easier on the steps.

Explanation:

#-10(x+5)+76=-12#

Get rid of brackets by multiplying the coefficient with the digits in the brackets.

#-10x-50+76=-12#
#-10x+26=-12#

Unknowns: one side, knowns: another.

#-10x=-12-26#
#-10x=-38#
Since the both sides are negative, let's multiply them by #(-1)# to get rid of a negative sign.

#-10x =-38 |(-1)#
#10x=38#

Now, do just a division:
#x=38/10#
#x=3.8#