3

Set 3: Quadratic Equations (Advanced)

Explanation

Answer: A

PROBLEM

Solve: x squared - 10x + 21 = 0. Find the larger root.

Solve: x squared - 10x + 21 = 0. Find the larger root.

A.

7

✓ Correct
B.

8

C.

5

D.

14

Detailed Explanation

Choice A is the best answer. Factor: (x - 7)(x - 3) = 0. Roots are 7 and 3. Larger: 7

Why others are wrong:
B: 8 is incorrect because it does not satisfy the equation.
C: 5 is incorrect because it does not satisfy the equation.
D: 14 is incorrect because it does not satisfy the equation.