SOLUTION: Use the distributive property to write each of the following expressions as the sum of monomials. (x-4)(x+5)

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Use the distributive property to write each of the following expressions as the sum of monomials. (x-4)(x+5)       Log On


   

Question 786316: Use the distributive property to write each of the following expressions as the sum of monomials.
(x-4)(x+5)
Answer by josgarithmetic(39625) About Me  (Show Source):
You can put this solution on YOUR website!
This should be no big trick. What if you assign one of the binomials to a variable?
Let h=(x-4).
Then you have h(x+5)
hx%2Bh%2A5
xh%2B5h
Now replace the substituted variable with the assigned expression:
x%28x-4%29%2B5%28x-4%29
x%5E2-4x%2B5x-20
x%5E2%2Bx-20--------your final result