How do you solve $(-5x + 4) - 5 = -4(x - 7)$ ?

Question

1832 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2015-11-26T14:59:40

Previous solutions but in a bit more detail

The brackets on the left only group numbers. The brackets on the right are part of multiplication.

$color(blue)(Step1)$
Ungroup the left and multiply out the right

$-5x+4-5 = -4x+7$
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
$color(blue)(Step2)$
Add $color(brown)(5x)$ to both sides

$color(brown)(5x) -5x +4-5=-4xcolor(brown)(+5x)-7$

$0+4-5=x-7$
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
$color(blue)(Step3)$
Add $color(brown)(7)$ to both sides

$4-5color(brown)(+7)=x-7color(brown)(+7)$
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
$color(blue)(Step4)$
Finish off the arithmetic

$6=x$
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
$color(blue)(Step5)$
Write in the equation in the standard way

#x=6

How do you solve (-5x + 4) - 5 = -4(x - 7)(-5x + 4) - 5 = -4(x - 7)?