Factorize : x2-21x+108

Matching exercise

    
Match the items on the right to the items on the left.
Step 1
Step 2
Step 3
Step 4
x2-21x+108=x2-12x-9x+108
=x2-12x-9x-108
=x(x-12)-9(x-12)
=(x-12)(x-9)