so factor
if you have ax^2+bx+c then to factor find
x+y=b
xy=ac
so
a=2
b-03
c=-9
2 times -9=-18
factor -18
-1,18
-2, 9
-3, 6
now add and find the one that adds to -3
-1+18=17
-2+9=7
-3+ 6=3, could work, if signs are reversed
so the numbers are -6 and 3
split -3 up
2x^2-6x+3x-9
group
(2x^2-6x)+(3x-9)
undistribute
(2x)(x-3)+(3)(x-3)
reverse distributive property
ab+ac=a(b+c)
(2x+3)(x-3)
so we can't do anything else because it isn't an equation so it has non meaning
if it does equal zero then
xy=0 then x and/or y=0 so
(2x+3)(x-3)=0 so
2x+3=0 and x-3=0 so
2x+3=0
subtract 3 from both sides
2x=-3
divide by 2
x=-1.5
x-3=0
add 3 to both sides
x=3
x=-1.5 or 3
