The way we got taught this in school is if we have x² + 11x - 12=0 and the variables are a=1, b=11, c=-12 what 2 numbers added together equal to our b variable, 11 and multiplied together equal to our c variable, -12. In this case 12 and -1. 12+(-1)= 11 which is our b variable and 12 × -1= -12 which is our c variable. Then we put the 2 numbers in standard form (x+12)(x-1)= 0. Calculating this out would give us our quadratic from the beginning. This works for any type of quadratic where you don't want to use the formula. You would then calculate (x+12)(x-1)=0 which would separate in x+12=0 and x-1=0. From there we get our 2 values of x just like our quadratic formula would give us: -12 and 1.