Answer:
you use the FOIL method
Explanation:
First
Inner
Outer
Last
you just distribute the numbers to all of the others then simplify.
ex.
(x+4)^2
(x+4)(x+4)
x^2+4x+4x+16
x^2+8x+16
in this, x times x is x^2. then x times 4 is 4x and 4 times x is 4x and 4 times 4 is 16. then combine like terms