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

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

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

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

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x^{2} = 21 - 4 x

x = 3, x = - 7

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} : 3

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

The solutions to the quadratic equation are:

x = 3, x = - 7

(x - 1) (x + 12) = 42

- 3 y + 4 = y^{2}

3 (x + 2) (x - 2) = (x - 4) 2 + 8 x

3 x^{2} + 27 x + 54 = - \frac{3 x ^{2}}{2} - \frac{27 x}{2} - 27

t, 48 = 8 (t) + 16 (t)^{2}

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