How do you simplify #(3m-5)(4m+9)#?

1 Answer
Jul 10, 2016

#12m^2 + 18m - 45#

Explanation:

Multiply out by "FOILing".

FOILing is when your multiply two binomials using a specific order.

F irst
O utside
I nside
L ast

#(a + b)(c + d) = ac + ad + bc + bd#

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Now let's FOIL #(3m-5)(4m + 9)#.

#(3m-5)(4m + 9)#

#(3m)(4m) + (3m)(9) -(5)(4m) - (5)(9)#

#12m^2 + 27m -9m - 45#

#12m^2 + 18m - 45#