Question

Evaluate the expression 3xy-2x^2 x=4 and y=3

Answer 1

3 × 4 × 3 - 2 × 4²

36 - 2 × 4²

36 - 2 × 16

36 - 32

The answer is 4

Is that right? I hoped it helped...

Answer 2

Okay, so first, you have to plug the X's and the Y's back into the equation, for example, in your problem:

3xy - 2x^2

X = 4

Y = 3

Plug the X's where the Variable X is listed, for example:

3 ( 4 ) y - 2 ( 4^2)

Then, plug in for the variable Y, as well:

3 ( 4 ) ( 3 ) - 2 ( 4^2)

Now, solve:

3 times 4 is 12 and 12 times 3 equals 36,


So, 3 (4)(3) = 36,

then, -2 (4^2),

4^2 equals 8, times -2 equals -16.

So, 36 - 16 = 20.

The answer is 20.