Factor: m^2 - 20m - 21

(m-21)(m+1)

Step-by-step explanation:

To factor this trinomial, find two numbers that multiply to -21 and add to -20:

(-21)(1)=-21

-21+1=-20

They are -21 and 1.

Add -21 and 1 to m to get both factors:

(m+(-21)) and (m+1)

(m-21) and (m+1)

Multiply them to get the

(m-21)(m+1)

Justification of step A: common denominator

Justification of step B: multliplication property of equality

Step-by-step explanation:

i got it right.