Explain how you find the Least Common Denominator of x^2+5x+4 and x^2-16

Answer 1

First factor the two quadratics:

x² + 5x + 4 = (x + 4)(x + 1)

x² - 16 = (x + 4)(x - 4)

The Least Common Denominator will have everything from both - but not duplicated. So, that would be:

(x + 4)(x + 1)(x - 4)

Notice that this has the (x + 4) and the (x + 1) and it also has the (x + 4) and the (x - 4)