Respuesta :

a² - a - 20 = 
= a² - 5 a + 4 a - 20 =
= a ( a - 5 ) + 4 ( a - 5 ) = 
= ( a - 5 ) ( a + 4 ) 
The zeroes are: a = -4, a = 5.

For this case we have the following polynomial:

[tex]a ^ 2 - a - 20[/tex]

We must factor the polynomial.

To do this we look for two numbers that are added equal to -1 and multiplied equal to -20.

Factoring we have:

[tex]a ^ 2 - a - 20 = (a-5) (a + 4)[/tex]

Answer:

The factored expression is given by:

[tex]a ^ 2 - a - 20 = (a-5) (a + 4)[/tex]