Find the exact solution of the following quadratic equation by using the Quadratic Formula.
1. x2 – 7x = 60
2. -x2 + 7x + 11 = 0
Find the value of the discriminant. Then describe the number and type of roots for the equation.
3. -4x2 – 14x + 3 = 0
4. x2 – 3x + 8 = 0
5. What are the solutions of 5x2 – 16 = 0
Answers (1. {-5, 12} 2. see below 3. The discriminant is 244. Because the discriminant is greater than 0 and is not a perfect square, the roots are real and irrational. 4. The discriminant is –23. Because the discriminant is less than 0, the two roots are complex. 5. plus or minus 4 times the square root of 5 over 5.)
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