.x^2+7x+12
=(x+3)(x+4)
x^2-7x+6
=(x-1)(x-6)
x^+3x-28
=(x+7)(x-4)
y^-7y+12
=(y-3)(y-4)
m^2+7m-18
=(m+9)(m-2)
p^2-5p-36 ^
=(p-9)(p+4)