Question

What does the middle term have to be in this trinomial to make it a perfect square? x^2+?+4

Answer 1

A perfect square is an expression in this form:

$(a+b)^2=a^2+2ab+b^2$

So, we have two perfect squares, and twice the product of the roots.

We have the two perfect squares: $x^2$ is the square of $x$, and 4 is the square of 2.

So, our perfect square can be completed in one of the two following ways:

$x^2-4x+4 = (x-2)^2,\quad x^2+4x+4 = (x+2)^2$

Answer 2

Answer: 4x

Step-by-step explanation:

Formula: a^2+2ab+b^2.

So in this case our a^2 is x^2. our b^2 is 4.

To find the middle term (2ab) we do 2*x*2 = 4x