What are the solutions to the equation x^2=21+4x ?

The solutions to the equation x^2=21+4x are x=7,x=-3

Find the zeros of x^2=21+4x

The zeros of x^2=21+4x are x=7,x=-3

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x^{2} = 21 + 4 x

x = 7, x = - 3

Solution steps

x^{2} = 21 + 4 x

Move

4 x

to the left side

x^{2} - 4 x = 21

Move

21

to the left side

x^{2} - 4 x - 21 = 0

Solve with the quadratic formula

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

(- 4)^{2} - 4 \cdot 1 \cdot (- 21) = 10

x_{1, 2} = \frac{- ( - 4 ) \pm 10}{2 \cdot 1}

Separate the solutions

x_{1} = \frac{- ( - 4 ) + 10}{2 \cdot 1}, x_{2} = \frac{- ( - 4 ) - 10}{2 \cdot 1}

x = \frac{- ( - 4 ) + 10}{2 \cdot 1} : 7

x = \frac{- ( - 4 ) - 10}{2 \cdot 1} : - 3

The solutions to the quadratic equation are:

x = 7, x = - 3

x^{2} + 10 x y - 24 y^{2}

3 y^{2} - 19 y - 14

x^{2} - 14 x + 31 = 63

x^{2} - 18 x - 19

x^{2} - 4 x = 45

What are the solutions to the equation x^2=21+4x ?
The solutions to the equation x^2=21+4x are x=7,x=-3
Find the zeros of x^2=21+4x
The zeros of x^2=21+4x are x=7,x=-3