How do you solve #2x ^ { 2} + 32= - 16x#?

1 Answer
Sep 15, 2017

#-4#

Explanation:

#2x^2+32=-16x# <- This is your equation
We will add #16x# to both sides.
That will become
#2x^2+32color(blue)+color(blue)16color(blue)x=-16xcolor(blue)+color(blue)16color(blue)x#

Now simplify it to become
#2x^2+32+16x=0#
Now we will solve this quadratic equation by factoring.
#2x^2+32+16x#
#= 2(x^2+8x+16)#
------->#x^2+8x+16#
Then, we break this equations into groups.
#x^2+8x+16 = (x^2+4x)+(4x+16)# (The #8x# was separated #4x# in each side)

Then we factor out #x# from #x^2+4x# and #4# from #4x+16#.
Which gives us #x(x+4)+4(x+4)#
Then we factor out #(x+4)# to give us #(x+4)(x+4)#.
Which is #2(x+4)(x+4)# and is also #2(x+4)^2#
So, #2(x+4^2)=0#
Now, #x+4=0#.
Now we subtract #4# from both sides.
#x+4color(blue)-color(blue)4=0color(blue)-color(blue)4#
Then we simplify to #x=-4#
So, the answer is #-4#.