-x²+7x+8=0

To solve the equation -x² + 7x + 8 = 0, you can use the quadratic formula:

x = (-b ± √(b² - 4ac)) / (2a)

In this equation, a = -1, b = 7, and c = 8.

Plugging these values into the formula, we get:

x = (-(7) ± √((7)² - 4(-1)(8))) / (2(-1)) = (-7 ± √(49 + 32)) / (-2) = (-7 ± √81) / (-2)

Simplifying further:

x = (-7 + 9) / (-2) = 2 / (-2) = -1

x = (-7 - 9) / (-2) = -16 / (-2) = 8

So, the two solutions to the equation -x² + 7x + 8 = 0 are x = -1 and x = 8.