How do you factor -x^2+15x-50=0x2+15x50=0?

1 Answer
May 3, 2015

-x^2+15x-50 = 0x2+15x50=0
or, equivalnetly
(-1)(x^2-15x+50) = 0(1)(x215x+50)=0

We are looking for two constants: aa and bb such that
a+b= -15a+b=15
and
axxb = 50a×b=50

The obvious pair is (a,b) = (-5,-10)(a,b)=(5,10)
gives us
-x^2+15x-50 = 0x2+15x50=0
-= (-1)(x-5)(x-10) = 0(1)(x5)(x10)=0

Note that it is unusual to be asked to factor an equation; normally we only factor expressions:
-x^2+15x-50 = (-1)(x-5)(x-10)x2+15x50=(1)(x5)(x10)

It may be that the intent was to extract
x-5 = 0x5=0
and
x-10=0x10=0
as factors of the original equation (check with your instructor).