What is the value of the expression 2x²+3xy-4y² when x = 2 and y = - 4?

Solution:

2x²+3xy-4y² (Given)

Substituting the values in the expression as x = 2 and y = - 4

2(2)² + 3(2)(-4) - 4(-4)²

On further simplification, we get

= 2 × 4 -24 - 4(16)

= 8 - 24 - 64

= 8 - 88

= - 80

Therefore, the value of the expression is - 80.

What is the value of the expression 2x²+3xy-4y² when x = 2 and y = - 4?

Summary:

The value of the expression 2x²+3xy-4y² when x = 2 and y = - 4 is - 80.