Question

(x²y + xy) (4xy - 7y)
​

Answer 1

Answer:

(x^2y+ xy) ( 4xy - 7y)

=4x^3y^2 - 7x^2y^2 + 4x^2y^2 - 7xy^2

= xy^2( 4x^2 - 3x - 7)

when x = -1

= -1y^2 [ 4(-1)^2 - 3(-1) - 7 ]

= 0

when x = 7/4,

= 7/4y^2 [ 4(7/4)^2 - 3(7/4) - 7 ]

= 7/4y^2 [0]

=0

Answer is 0