first.
look for when all are postive, or only two are negative. Think out why.
if x>19, all are positive.
Now, when one is positive, and two are negative. What if x>-11 and x<18?
1. Solve (x+19)(x-11)(x+18)>0
2. Solve the equation 2x^2-x=-7
1 answer
2 answers