Question 144397
{{{2x^3-3xy}}} Start with the given expression



{{{2(-1)^3-3(-1)(2)}}} Plug in {{{x=-1}}} and {{{y=2}}}



{{{2(-1)-3(-1)(2)}}} Cube -1 to get -1



{{{-2-3(-1)(2)}}} Multiply 2 and -1 to get -2



{{{-2-3(-2)}}} Multiply -1 and 2 to get -2



{{{-2+6}}} Multiply -3 and -3 to get +6



{{{4}}} Add -2 and 6 to get 4




So {{{2x^3-3xy=4}}} when {{{x=-1}}} and {{{y=2}}}