1. Solving Quadratic Equations

2. 1. Solve. x2 = 100 Take the square root of both sides.
Do not forget the ±.
The solution set has two answers.

3. 2. Solve. x2 = 20 Take the square root of both sides.
Do not forget the ±.
Simplify the square root.
The solution set has two answers.

4. 3. Solve. y2 = -64 Anticipate imaginary solutions.
Take the square root of
both sides.
Do not forget the ±.
Simplify the square root.
The solution set has two answers.

5. 4. Solve. (x + 1)2 = 4
Work it twice ±.

6. 5. Solve this quadratic equation by factoring.
Zero factor

7. 6. Solve this quadratic equation by completing the square.
x2 + 10x + 24 = 0
x2 + 10x + _______ = ________
( x + _____)2 = ______
x + _____ = ± _______
x = ________
x = {______, ______} 25 25 5 1 5 1
-5 ± 1 -6 -4

8. 7. Solve. x2 = -81 Anticipate imaginary solutions.
Take the square root of
both sides.
Do not forget the ±.
Simplify the square root.
The solution set has two answers.

9. 8. Which of the following equations has a solution set of x = {9, -5}?
x=9, x=-5
(x – 9)(x + 5) = 0
x2 – 4x – 45 = 0
A. x2 + 4x + 45 B. x2 + 4x – 45 C. x2 – 4x – 45
D. x2 – 4x + 45

10. 9. What is the sum of the solutions to the quadratic y2 – 15y +56=0?
Hence…
7 + 8 = 15
A. 3
B. -3
C. 15
D. -15

11. 10. The quadratic equation x2 + 5x + 25/4 = 0 has…
D = b2 – 4ac
D = (5)2 – 4(1)(25/4)
D = 25 – 25
D = 0
A. one real rational solutions.
B. two real irrational solutions.
C. two real rational solution.
D. two complex solutions.
E. one complex solution.