Question

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

Answer 1

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.

Answer 2

x = 9.6

x = - 2.6

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=(7±√(49-4((1)(-25)) ) )/(2(1))`

`x=(7±√(49+100 ) )/(2(1))`

`x=(7±√(149 ) )/(2)`

`x=(7±12.2)/(2)`

Two separate equations

`x=(7+12.2)/(2)`

`x=(7-12.2)/(2)`

`x=(7+12.2)/(2)`

`x=(19.2)/(2)`

x = 9.6

`x=(7-12.2)/(2)`

`x=(-5.2)/(2)`

x = - 2.6