SOLUTION: I have a fair understanding of finding discriminants but I am stumped on one. x square - 15 = 0

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: I have a fair understanding of finding discriminants but I am stumped on one. x square - 15 = 0      Log On


   

Question 958622: I have a fair understanding of finding discriminants but I am stumped on one.
x square - 15 = 0
Found 2 solutions by josgarithmetic, macston:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
You use what you already know.
x%5E2-15=0, so what is the discriminant? Maybe you need the whole expanded form of the equation?

x%5E2%2B0%2Ax-15=0

1%2Ax%5E2%2B0%2Ax-15=0------Does this look better?
Corresponds to
ax%5E2%2Bbx%2Bc=0.

Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
ax%5E2%2Bbx%2Bc=0
Discriminant=b%5E2-4ac=%280%29%5E2-4%281%29%28-15%29=-4%28-15%29=60
Discriminant=60