4x2-x-18=0
2 years ago
4X2-X-18=0 we need to multiply 4 and -18 which gives -72.
4x2+8x-9x-18=0 then we find two different numbers that we multiply together to get -72x, and add them to get -x. 8x(-9)=-72 and 8x-9x=-x
We replace the "-x" with "8x-9x"
4x(x+2)-9(x+2)=0 We factor out the like terms.
(4x-9)(x+2)=0 If x= 9/4 or -2 is put in the original equation, it would equal 0.
x=9/4 or x=-2
2 years ago
Answered By Ola B
4X2-X-18=0 we need to multiply 4 and -18 which gives -72.
4x2+8x-9x-18=0 then we find two different numbers that we multiply together to get -72x, and add them to get -x. 8x(-9)=-72 and 8x-9x=-x
We replace the "-x" with "8x-9x"
4x(x+2)-9(x+2)=0 We factor out the like terms.
(4x-9)(x+2)=0 If x= 9/4 or -2 is put in the original equation, it would equal 0.
x=9/4 or x=-2