Question

Use the quadratic formula to solve x^2 + 9x + 10 = 0. Estimate irrational solutions to the nearest tenth.

Answer 1

Basically, just plus your numbers into quadratic formula. A= 1, B= 9, C= 10.
The answer you will get is B.

Answer 2

$x^{2} + 9x + 10 = 0 \\x = \frac{-(9) +/- \sqrt{(9)^{2} - 4(1)(10)}}{2(1)} \\x = \frac{-9 +/- \sqrt{81 - 40}}{2} \\x = \frac{-9 +/- \sqrt{41}}{2} \\x = \frac{-9 +/- 6.4}{2} \\x = \frac{-9 + 6.4}{2} \\x = \frac{-2.6}{2} \\x = -1.3 \\ \\x = \frac{-9 - 6.4}{2} \\x = \frac{-15.4}{2} \\x = -7.7$

It is equal to B.