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

The solutions to the equation x^2=8x-21 are x=4+sqrt(5)i,x=4-sqrt(5)i

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

The zeros of x^2=8x-21 are x=4+sqrt(5)i,x=4-sqrt(5)i

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x^{2} = 8 x - 21

x = 4 + 5 i, x = 4 - 5 i

Solution steps

x^{2} = 8 x - 21

Move

21

to the left side

x^{2} + 21 = 8 x

Move

8 x

to the left side

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

Write in the standard form

a x^{2} + b x + c = 0

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

Solve with the quadratic formula

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

Simplify

(- 8)^{2} - 4 \cdot 1 \cdot 21 : 25 i

x_{1, 2} = \frac{- ( - 8 ) \pm 2 5 i}{2 \cdot 1}

Separate the solutions

x_{1} = \frac{- ( - 8 ) + 2 5 i}{2 \cdot 1}, x_{2} = \frac{- ( - 8 ) - 2 5 i}{2 \cdot 1}

x = \frac{- ( - 8 ) + 2 5 i}{2 \cdot 1} : 4 + 5 i

x = \frac{- ( - 8 ) - 2 5 i}{2 \cdot 1} : 4 - 5 i

The solutions to the quadratic equation are:

x = 4 + 5 i, x = 4 - 5 i

\frac{x - 1}{2} = \frac{x + 3}{3}

10 m + 3 (n - 8) - 7 (m - 12) + 9 n

30 \cdot 20

2 \leq 20

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

What are the solutions to the equation x^2=8x-21 ?
The solutions to the equation x^2=8x-21 are x=4+sqrt(5)i,x=4-sqrt(5)i
Find the zeros of x^2=8x-21
The zeros of x^2=8x-21 are x=4+sqrt(5)i,x=4-sqrt(5)i