Question

Factorise 49m²-84mn+36n² using the identity x²+(a+b)x+ab=(x+a)(x+b)​

Answer 1

(7m-6n)(7m-6n)

Explanation:

Given the expression 49m²-84mn+36n², this can also be written as;

49m²-84mn+36n²

= 7²m² - 84mn + 6²n²

= (7m)²-2*7m*6n+ (6n)²

= (7m-6n)²

= (7m-6n)(7m-6n)

Hence the expanded form is (7m-6n)(7m-6n)