MA.912.A.7.2: Solve quadratic equations by factoring and using the quadratic formula.

f(x) = −x2 + 10x − 21

The function below can be used to describe the motion of a ball thrown through the air.

Which of the following shows the correct factorization of this function for f(x) = 0?

A.(x + 3)(x + 7) = 0 B.(x + 3)(x − 7) = 0 C.(−x + 3)(x − 7) = 0 D.(x − 3)(x + 7) = 0

MA.912.A.7.2: Solve quadratic equations by factoring and using the quadratic formula.

Which equation below could be used to solve the function

f(x) = x2 + x − 20 for x, if f(x) = 10?

A. (x + 5)(x + 4) = 10 B. (x − 5)(x − 4) = 10 C. (x + 6)(x − 5) = 0 D. (x + 5)(x − 6) = 0

MA.912.A.7.2: Solve quadratic equations by factoring and using the quadratic formula.

Daryl needs to solve the problem shown below by using the quadratic formula.

x2 + 7x + 1 = 31Which of the following shows the quadratic formula being used correctly to determine the solutions for this problem?

MA.912.A.7.2: Solve quadratic equations by factoring and using the quadratic formula.

Judith used a quadratic function to solve a problem. The factored form of the function is shown below.(x − 3)(x − 4) = 0What is the sum of the solutions to the problem?

A. 3 B. 1C. 7 D. 12

MA.912.A.7.2: Solve quadratic equations by factoring and using the quadratic formula.

Andrea used a quadratic function to solve a problem. The factored form of the function is shown below.

(4x + 8)(6x − 3) = 0What is the positive solution to the problem?

A. -2 B. 0.5C. 2D. 5