Multiply each polynomial

(x + 5) (x+4)

teach me step by step

Answer: x^2 + 9x + 20

Step-by-step explanation:

Foil Method: (a + b) (c + d) = ac + ad + bc + bd

Lets say:

a = x

b = 5

c = x

d = 4

Plugging in the numbers: xx + 4x + 5x + 5*4

Combine like terms:

xx = x^2

4x + 5x = 9x

5 * 4 = 20

You're then left with: x^2 + 9x + 20