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

The solutions to the equation x^2+2x-21=0 are x=-1+sqrt(22),x=-1-sqrt(22)

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

The zeros of x^2+2x-21=0 are x=-1+sqrt(22),x=-1-sqrt(22)

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

x = - 1 + 22, x = - 1 - 22

Decimal Notation

x = 3.69041 \dots, x = - 5.69041 \dots

Solution steps

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

Solve with the quadratic formula

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

2^{2} - 4 \cdot 1 \cdot (- 21) = 222

x_{1, 2} = \frac{- 2 \pm 2 22}{2 \cdot 1}

Separate the solutions

x_{1} = \frac{- 2 + 2 22}{2 \cdot 1}, x_{2} = \frac{- 2 - 2 22}{2 \cdot 1}

x = \frac{- 2 + 2 22}{2 \cdot 1} : - 1 + 22

x = \frac{- 2 - 2 22}{2 \cdot 1} : - 1 - 22

The solutions to the quadratic equation are:

x = - 1 + 22, x = - 1 - 22

4 k^{2} - 9 = 0

6 x^{2} - x - 2 = 0

3 x^{2} + 18 x = - 24

4 m^{2} = 2 - 4 m

5 x^{2} + 4 = 49

What are the solutions to the equation x^2+2x-21=0 ?
The solutions to the equation x^2+2x-21=0 are x=-1+sqrt(22),x=-1-sqrt(22)
Find the zeros of x^2+2x-21=0
The zeros of x^2+2x-21=0 are x=-1+sqrt(22),x=-1-sqrt(22)