Question 521604: (x+4)(x-5) If you were to multiply the two factors in the expression,which operation would you perform first? x(x), x(-5), 4(x), 4(-5)
Answer by jlshires(17)   (Show Source):
You can put this solution on YOUR website! FOIL- First, outer, Inner, Last
(x+4)(x-5)
do the first in both groups- x(x), then the outer in both groups (the first x and five) x(-5), then the inner in both groups (4 and the second x) 4(x), then the last in both groups (4)(-5)
so you would get x(x)+x(-5)+4(x)+4(-5)
combined it is x^2-5x+4x-20 or x^2-x-20
***Make sure that when there is a subtraction in the problem, like this one, you treat it as a negative number. If you keep it as x+(-5) it will help you when you are figuring out what the correct signs are.
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