107k views
3 votes
Which equation is equivalent to x2 + 36x= 88?

User Tomk
by
3.6k points

1 Answer

3 votes

We must complete the square in order to solve the problem.

Now, the first step is to realize that if we have factor a quadratic (x+a)^2


(x+a)^2=x^2+2ax+a^2^{}

which, in our case, implies


2ax=36x
\therefore a=18

Therefore, we add 18^2 to both sides of the equation such that


x^2+36x\textcolor{#FF7968}{+18^2}=(x+18)^2

this gives


x^2+36x+18^2=88+18^2
\textcolor{#FF7968}{\Rightarrow(x+18)^2=412}

which is choice c from the options.

User Ideaboxer
by
3.3k points