Question

sarath says that the expression ^2+6+3^2 cannot be factored using the identity(+)^2? Do you agree with Sarath? If you agree with Sarath, then can you modify the middle term of the expression such that it becomes factored using the identity (+)^2.

Answer 1

Example 1: Factorise 21a2b + 27ab2

Solution: We have: 21a2b = 7*3*a*a*b

27ab2 = 3*3*3*a*b*b

The two terms have 3, a and b as common factors.

Therefore, 21a2b + 27ab2 = (3*a*b*7*a) + (3*a*b*3*b*3)

= 3*a*b*[(7*a) + (9*b)] (combining the terms)

= 3ab*(7a + 9b)