Question

The quadratic function y = -x² - 10x - 8 models the height of a trestle on a bridge. The x-axis represents ground level. To find where the section of the bridge meets ground level, solve 0=−x² - 10x - 8. Where does this section of the bridge meet ground level? Choose an equation that would be used to solve 0=−x² - 10x - 8

a. x=−x² - 10x - 8
b. 0=−x² - 10x - 8
c. x² +10x + 8=0
d. y=−x² - 10x - 8

Answer 1

To find where the section of the bridge meets ground level, we can solve the equation -x² - 10x - 8 = 0 using the quadratic formula. The two possible values for x are -2 and -8.

Step-by-step explanation:

To find where the section of the bridge meets ground level, we need to solve the equation 0 = -x² - 10x - 8.

To solve this quadratic equation, we can use the quadratic formula: x = (-b ± √(b² - 4ac)) / 2a.

Plugging in the values from our equation, we get x = (-(-10) ± √((-10)² - 4(-1)(-8))) / 2(-1).

Simplifying further, we get x = (10 ± √(100 - 32)) / -2, which gives us two possible values for x: -2 and -8.