Question 151636
{{{3P - 4Q}}} Start with the given expression.



{{{3(3y + 7xy - 2x) - 4(9 - 2y)}}} Plug in P = 3y + 7xy - 2x. Plug in Q = 9 - 2y



{{{9y + 21xy - 6x - 36 +8y}}} Distribute



{{{-6x + 21xy+17y - 36}}} Combine like terms.



So {{{3P - 4Q=-6x + 21xy+17y - 36}}}