How do you multiply #(3x ^ { - 9} y ^ { 4} ) ( - 2x ^ { 2} y ^ { 7} )#?

1 Answer
Jun 11, 2017

#-6x^-7y^11#

Explanation:

When expanding terms like this, multiply the like terms together ie. multiply constants together, multiply unknown terms together.

#(3) (-2) = -6#

When multiplying like terms with exponents, you add the exponents together.

#(x^-9) (x^2) = x^(-9+2) = x^(-7)#

#(y^4) (y^7) = y^(4+7) = y^11#

End result:

#(3x^-9y^4)(-2x^2y^7) = -6x^-7y^11#