Question

Can you explain how to do this math problem?

Answer 1

Since the problem is 2x^2-5xy-y^3 we first have to plug in what the x and y stands for, once you do that your problem should look like this:

2(-3)^2- 5(-3)(-2)- (-2)^3

Now take the parentheses away and when you do that your signs change.

2x3^2-5x(-3)x(-2)-(-2)^3    

do it again with -5x(-3)x(-2)

2x3^2-30-(-2)^3

now do this with (-2)^3

2x3^2-30-(-8)

Now evaluate the power

3^2 becomes 9

2x9-30-(-8)

then change -(-8) to a positive since two negatives make a positive

2x9-30+8

Now multiply the numbers 2x9

18-30+8

Then do 18-30 which equals -12 then add 8

Now you are left with your answer:

-4

Hope this helps! :3