Question

Find the product by using suitable identity :- (x - 5)(x +4)​

Answer 1

Solution :-

➤ (x-5) (x+4)

➤ x^2 + 4x - 5x - 20

➤ x^2 -x - 20

Answer 2

Using identity IV, the product can be find out

(x-a)(x+b)=$x^{2}$ + x(a+b)  ab

(x-5)(x+4)=$x^{2}$ + x(-5+4)  (-5)*4

=$x^{2}$ -x - 20

Happy Studying!!!