Discriminant
What is the formula to find the discriminant?
b^2-4ac
Solve the following quadratic equation by factoring.
x2 - 6x + 5 = 0
x= {1, 5}
Solve the following quadratic equation by completing the square:
x2 + 6x = -8
x = {-4, -2}
When is it best to use the square root method for solving quadratics?
When there is no 'b' term.
What is the quadratic formula?
x = -b +- sqrt(b2 - 4ac) /(2a)
What is the discriminant:
5b^2 + b − 2 = 0
41
Solve the following quadratic equation by factoring:
9x2 - 81x = 0
x = {0, 9}
Solve the following quadratic equation by completing the square:
x2 - 6x = -5
x = {1, 5}
Solve using square roots:
x^2-81=0
x=+-9
Solve the following quadratic equation by using the quadratic formula:
6x2 - 19 = 5
x = ±2
What is the discriminant:
−4m^2 − 4m + 5 = 0
96
Solve the following quadratic equation by factoring.
3n2 - 25n + 28=0
x= {4/3, 7}
Solve the following quadratic equation by completing the square:
x2 - 2x = 24
x = {-4, 6}
Solve using square roots:
2x^2-200=0
x=+-10
Solve the following quadratic equation by using the quadratic formula: x2 -2x -48 = 0
x = -6, 8
Using the discriminate, which method should you use to solve this quadratic?
9m^2 + 6m + 6 = 5
Factoring (discriminate equals zero)
Solve the following quadratic equation by factoring.
9x2 + 10x - 30= 7x
x= {5/3, -2}
Solve by completing the square:
2x^2-16x=-30
x={3,5}
Solve using square roots:
5x^2-11=234
x=+-7
Solve the following quadratic equation by using the quadratic formula:
6x^2+17x+12=0
x= -3/2, -4/3
Using the discriminate, which method should you use to solve this quadratic?
−4r^2 − 4r = 6
Quadratic formula (discriminate is -80)
Solve the following quadratic equation by factoring.
28b2 - 348 =-5
x= {-7/2, 7/2}
Solve by completing the square:
x2 + 8x - 20 = 0
x = {-10, 2}
Solve using square roots:
4x^2-39=10
x=+-7/2
Solve the following quadratic equation by using the quadratic formula:
10x^2-19=5
x=
+-(2sqrt15)/5