SOLUTION: 1) Use a variety of ways to show that x^2-2x-15=0 has two solutions. 2) Explain how changing one number in the equation x^2-2x-15=0 can result in no solution. Justify your answe

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: 1) Use a variety of ways to show that x^2-2x-15=0 has two solutions. 2) Explain how changing one number in the equation x^2-2x-15=0 can result in no solution. Justify your answe      Log On


   

Question 759367: 1) Use a variety of ways to show that x^2-2x-15=0 has two solutions.
2) Explain how changing one number in the equation x^2-2x-15=0 can result in no solution.
Justify your answer.
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
#2 is a question about the discriminant.

ax%5E2%2Bbx%2Bc=0 has no solution (more correctly stated, no real solution) if b%5E2-4ac%3C0. You are free to choose any value that will work in your problem exercise. The discriminant in the current equation in your #2 is highlight%28%28-2%29%5E2-4%2A%28-15%29%29=4%2B60=64