What are the solutions to the equation 0.7x^2-4.2x-0.7=0 ?

The solutions to the equation 0.7x^2-4.2x-0.7=0 are x=3+sqrt(10),x=3-sqrt(10)

Find the zeros of 0.7x^2-4.2x-0.7=0

The zeros of 0.7x^2-4.2x-0.7=0 are x=3+sqrt(10),x=3-sqrt(10)

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0.7 x^{2} - 4.2 x - 0.7 = 0

x = 3 + 10, x = 3 - 10

Decimal Notation

x = 6.16227 \dots, x = - 0.16227 \dots

Solution steps

0.7 x^{2} - 4.2 x - 0.7 = 0

Multiply both sides by

10

7 x^{2} - 42 x - 7 = 0

Solve with the quadratic formula

x_{1, 2} = \frac{- ( - 42 ) \pm ( - 42 ) ^{2} - 4 \cdot 7 ( - 7 )}{2 \cdot 7}

(- 42)^{2} - 4 \cdot 7 (- 7) = 1410

x_{1, 2} = \frac{- ( - 42 ) \pm 14 10}{2 \cdot 7}

Separate the solutions

x_{1} = \frac{- ( - 42 ) + 14 10}{2 \cdot 7}, x_{2} = \frac{- ( - 42 ) - 14 10}{2 \cdot 7}

x = \frac{- ( - 42 ) + 14 10}{2 \cdot 7} : 3 + 10

x = \frac{- ( - 42 ) - 14 10}{2 \cdot 7} : 3 - 10

The solutions to the quadratic equation are:

x = 3 + 10, x = 3 - 10

- 4 x^{2} + 225 = 45

0.1 x^{2} + 0.4 x - 0.3 = 0

4 x^{2} + 4 (2 x + 1) = 0

- x^{2} - 56 = 0

0 = - 3 x^{2} + 2 x + 1

What are the solutions to the equation 0.7x^2-4.2x-0.7=0 ?
The solutions to the equation 0.7x^2-4.2x-0.7=0 are x=3+sqrt(10),x=3-sqrt(10)
Find the zeros of 0.7x^2-4.2x-0.7=0
The zeros of 0.7x^2-4.2x-0.7=0 are x=3+sqrt(10),x=3-sqrt(10)