What are the solutions to the equation 0=-0.04x^2+0.8x+9 ?

The solutions to the equation 0=-0.04x^2+0.8x+9 are x=-5(sqrt(13)-2),x=5(2+sqrt(13))

Find the zeros of 0=-0.04x^2+0.8x+9

The zeros of 0=-0.04x^2+0.8x+9 are x=-5(sqrt(13)-2),x=5(2+sqrt(13))

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0 = - 0.04 x^{2} + 0.8 x + 9

x = - 5 (13 - 2), x = 5 (2 + 13)

Decimal Notation

x = - 8.02775 \dots, x = 28.02775 \dots

Solution steps

0 = - 0.04 x^{2} + 0.8 x + 9

Multiply both sides by

100

0 = - 4 x^{2} + 80 x + 900

Switch sides

- 4 x^{2} + 80 x + 900 = 0

Solve with the quadratic formula

x_{1, 2} = \frac{- 80 \pm 8 0 ^{2} - 4 ( - 4 ) \cdot 900}{2 ( - 4 )}

8 0^{2} - 4 (- 4) \cdot 900 = 4013

x_{1, 2} = \frac{- 80 \pm 40 13}{2 ( - 4 )}

Separate the solutions

x_{1} = \frac{- 80 + 40 13}{2 ( - 4 )}, x_{2} = \frac{- 80 - 40 13}{2 ( - 4 )}

x = \frac{- 80 + 40 13}{2 ( - 4 )} : - 5 (13 - 2)

x = \frac{- 80 - 40 13}{2 ( - 4 )} : 5 (2 + 13)

The solutions to the quadratic equation are:

x = - 5 (13 - 2), x = 5 (2 + 13)

4 x^{2} - 15 x + 14 = 0

x^{2} - 10 = 4 x + 11

47 y^{2} = - 15 y

x^{2} - 10 x + 45 = 0

x^{2} + 8 x = - 7

What are the solutions to the equation 0=-0.04x^2+0.8x+9 ?
The solutions to the equation 0=-0.04x^2+0.8x+9 are x=-5(sqrt(13)-2),x=5(2+sqrt(13))
Find the zeros of 0=-0.04x^2+0.8x+9
The zeros of 0=-0.04x^2+0.8x+9 are x=-5(sqrt(13)-2),x=5(2+sqrt(13))