Question

Use a graphing utility to find or to approximate the​ x-intercepts of the graph of the function.
yequals5xsquaredminus14xplus8
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Part 1
Select the correct choice below​ and, if​ necessary, fill in the answer box to complete your answer.
A.
The​ x-intercept(s) is/are xequals
  
enter your response here.
​(Simplify your answer. Use a comma to separate answers as needed. Type an integer or decimal rounded to four decimal places as​ needed.)
B.
There is no​ x-intercept.

Answers

Answered by GPT-4o mini
To find the x-intercepts of the function \( y = 5x^2 - 14x + 8 \), we can set \( y = 0 \) and solve for \( x \):

\[
5x^2 - 14x + 8 = 0
\]

This is a quadratic equation in the standard form \( ax^2 + bx + c = 0 \) where \( a = 5 \), \( b = -14 \), and \( c = 8 \). We can use the quadratic formula to find the x-intercepts:

\[
x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}
\]

Substituting the values of \( a \), \( b \), and \( c \):

1. Calculate the discriminant \( b^2 - 4ac \):

\[
b^2 - 4ac = (-14)^2 - 4 \cdot 5 \cdot 8 = 196 - 160 = 36
\]

2. Now substituting back into the quadratic formula:

\[
x = \frac{14 \pm \sqrt{36}}{2 \cdot 5}
\]

\[
x = \frac{14 \pm 6}{10}
\]

3. This gives two possible solutions:

- First solution:

\[
x = \frac{14 + 6}{10} = \frac{20}{10} = 2
\]

- Second solution:

\[
x = \frac{14 - 6}{10} = \frac{8}{10} = 0.8
\]

Thus, the x-intercepts of the function are:

\[
x = 2 \quad \text{and} \quad x = 0.8
\]

### Conclusion

The correct choice is:

A. The x-intercept(s) is/are \( x = 2, 0.8 \) (approximate as needed).
B. There is no x-intercept is not applicable here since we have found two x-intercepts.

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