Question

Graphs of Quadratic Equations Practice
Complete this assessment to review what you’ve learned. It will not count toward your grade.
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Question
Given the quadratic equation y=5x2+8x+9
, solve for the y-coordinate of the parabola when x=−3
.(1 point)
(−3
,
)
Remaining Attempts : 3
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Answer 1

To find the y-coordinate of the parabola represented by the quadratic equation \( y = 5x^2 + 8x + 9 \) when \( x = -3 \), substitute \(-3\) into the equation:

\[
y = 5(-3)^2 + 8(-3) + 9
\]

Now, calculate each term step by step:

1. Calculate \((-3)^2\):
\[
(-3)^2 = 9
\]

2. Multiply by 5:
\[
5 \times 9 = 45
\]

3. Calculate \(8(-3)\):
\[
8 \times (-3) = -24
\]

4. Now put it all together:
\[
y = 45 - 24 + 9
\]

5. Combine the values:
\[
45 - 24 = 21
\]
\[
21 + 9 = 30
\]

Therefore, the y-coordinate when \( x = -3 \) is \( 30 \).

The point is:
\[
(-3, 30)
\]