Question

factorise m²+21m+90=0​

Answer 1

Answer:

m²+21m+90=0.

m²+15m+6m+90=0.

m(m+15)+6(m+15)=0.

(m+6)(m+15)=0.

m+6=0.

m=-6.

m+15=0.

m=-15.

I think this is your answer.

Answer 2

Step-by-step explanation:

m^2 + 21m + 90=0

m^2+ 15m +6m + 90 =0

m(m+15) + 6(m+15) = 0

m+6(m+15)