Question

x^{2}-7x-25=0 to the nearest tenth

Answer 1

Answer:

x = 9.6

x = - 2.6

Step-by-step explanation:

$x=\frac{-b±\sqrt{b^{2}-4ac } }{2a}$

Ignore the before the ± it wouldn't let me type it correctly.

x² - 7x - 25 = 0

a = 1

b = - 7

c = - 25

$x=\frac{-(-7)±\sqrt{-7^{2}-4((1)(-25)) } }{2(1)}$

$x=\frac{7±\sqrt{49-4((1)(-25)) } }{2(1)}$

$x=\frac{7±\sqrt{49+100 } }{2(1)}$

$x=\frac{7±\sqrt{149 } }{2}$

$x=\frac{7±12.2}{2}$

Two separate equations

$x=\frac{7+12.2}{2}$

$x=\frac{7-12.2}{2}$

$x=\frac{7+12.2}{2}$

$x=\frac{19.2}{2}$

x = 9.6

$x=\frac{7-12.2}{2}$

$x=\frac{-5.2}{2}$

x = - 2.6

Answer 2

For this just use the quadratic formula to find the zeros. In this case, you get 7 +/- square root 149 over 2. Which gives you -2.6 and 9.6.