Evaluating Functions: Finding x for f(x) = 3

The video tutorial explains how to solve for x in the function f(x) = -2x + 9, given that f(x) equals 3. The instructor substitutes 3 into the function, simplifies the equation using algebraic methods, and solves for x, finding that x equals 3.

What is the given function f(x)?

• f(x) = 2x + 9

• f(x) = -2x + 9

• f(x) = 2x - 9

• f(x) = -2x - 9

What value is f(x) equal to in the problem?

• 3

• 0

• 2

• 9

What is the first step in solving the equation after substituting the value?

• Subtract 9

• Add 9

• Divide by -2

• Multiply by 2

What is the result after subtracting 9 from both sides of the equation?

• 3

• -3

• -6

• 6

What is the value of x after solving the equation?

• 2

• 3

• -3

• -2