Examples
x2+8x+16x2+8x+16
Step 1
Rewrite 1616 as 4242.
x2+8x+42x2+8x+42
Step 2
Check that the middle term is two times the product of the numbers being squared in the first term and third term.
8x=2⋅x⋅48x=2⋅x⋅4
Step 3
Rewrite the polynomial.
x2+2⋅x⋅4+42x2+2⋅x⋅4+42
Step 4
Factor using the perfect square trinomial rule a2+2ab+b2=(a+b)2a2+2ab+b2=(a+b)2, where a=xa=x and b=4b=4.
(x+4)2(x+4)2