What are the solutions to the equation 2x^2-8x-21=0 ?

The solutions to the equation 2x^2-8x-21=0 are x=(4+sqrt(58))/2 ,x=(4-sqrt(58))/2

Find the zeros of 2x^2-8x-21=0

The zeros of 2x^2-8x-21=0 are x=(4+sqrt(58))/2 ,x=(4-sqrt(58))/2

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2 x^{2} - 8 x - 21 = 0

x = \frac{4 + 58}{2}, x = \frac{4 - 58}{2}

Decimal Notation

x = 5.80788 \dots, x = - 1.80788 \dots

Solution steps

2 x^{2} - 8 x - 21 = 0

Solve with the quadratic formula

x_{1, 2} = \frac{- ( - 8 ) \pm ( - 8 ) ^{2} - 4 \cdot 2 ( - 21 )}{2 \cdot 2}

(- 8)^{2} - 4 \cdot 2 (- 21) = 258

x_{1, 2} = \frac{- ( - 8 ) \pm 2 58}{2 \cdot 2}

Separate the solutions

x_{1} = \frac{- ( - 8 ) + 2 58}{2 \cdot 2}, x_{2} = \frac{- ( - 8 ) - 2 58}{2 \cdot 2}

x = \frac{- ( - 8 ) + 2 58}{2 \cdot 2} : \frac{4 + 58}{2}

x = \frac{- ( - 8 ) - 2 58}{2 \cdot 2} : \frac{4 - 58}{2}

The solutions to the quadratic equation are:

x = \frac{4 + 58}{2}, x = \frac{4 - 58}{2}

4 x^{2} - 371 = 29

3 x^{2} - 16 x + 2 = 0

6 x^{2} + 4 x - 5 = 0

x^{2} + 15 x = 6 x

3 x^{2} - x = - 4

What are the solutions to the equation 2x^2-8x-21=0 ?
The solutions to the equation 2x^2-8x-21=0 are x=(4+sqrt(58))/2 ,x=(4-sqrt(58))/2
Find the zeros of 2x^2-8x-21=0
The zeros of 2x^2-8x-21=0 are x=(4+sqrt(58))/2 ,x=(4-sqrt(58))/2