Question

Difficulty: EasyQuadratic Functions and Graphs

The quadratic function ff is defined by f(x)=3(x2)2+5f(x) = 3(x - 2)^2 + 5. In the xyxy-plane, the graph of y=f(x)y = f(x) intersects the yy-axis at the point (0,c)(0, c). What is the value of cc?

Answer: 17

Answer

The correct answer is 17.
To find the yy-intercept of the graph of y=f(x)y = f(x), we substitute x=0x = 0 into the equation: f(0)=3(02)2+5f(0) = 3(0 - 2)^2 + 5. Simplifying the expression inside the parentheses gives 3(2)2+53(-2)^2 + 5. Squaring 2-2 gives 44, making the expression 3(4)+5=12+5=173(4) + 5 = 12 + 5 = 17. Therefore, the graph intersects the yy-axis at the point (0,17)(0, 17), which means the value of cc is 17.

Step-by-Step Solution

1
Set x=0x = 0 to find the point where the graph intersects the yy-axis.
f(0)=3(02)2+5f(0) = 3(0 - 2)^2 + 5
The yy-intercept of any graph in the xyxy-plane occurs when the xx-coordinate is equal to 00.
2
Perform the arithmetic evaluation to find the value of f(0)f(0).
f(0)=17f(0) = 17
First, evaluate the term inside the parentheses: 02=20 - 2 = -2. Squaring 2-2 gives 44. Then, multiply 33 by 44 to get 1212. Finally, add 55 to obtain 1717.

Key Concept

Evaluating a quadratic function at x=0x = 0 to determine its yy-intercept.
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