SYNTENE LEARN . SAT MATH . ADVANCED MATH

The equation x^2 + 10x + c = 0 has exactly one real solution. What is the value of c?

Answer: 25. 100 - 4c = 0, so c = 25. The equation becomes (x + 5)^2 = 0.

Step-by-step solution

100 - 4c = 0, so c = 25. The equation becomes (x + 5)^2 = 0.

Common mistake

Setting the discriminant to a positive number, or dividing 100 by 4 incorrectly.

Watch: 20-second video walkthrough

What is the answer to The equation x^2 + 10x + c = 0 has exactly one real solution. What is the value of c?

Answer: 25. 100 - 4c = 0, so c = 25. The equation becomes (x + 5)^2 = 0.

How do you solve it?

100 - 4c = 0, so c = 25. The equation becomes (x + 5)^2 = 0.

What mistake do most students make?

Setting the discriminant to a positive number, or dividing 100 by 4 incorrectly.

What SAT topic is this?

Advanced Math. Practice more free Advanced Math questions with instant feedback at Syntene Learn.

Practice free SAT Math with instant feedback