What are the solutions to the equation 90=(x+8)(x+7) ?

The solutions to the equation 90=(x+8)(x+7) are x=2,x=-17

Find the zeros of 90=(x+8)(x+7)

The zeros of 90=(x+8)(x+7) are x=2,x=-17

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90 = (x + 8) (x + 7)

x = 2, x = - 17

Solution steps

90 = (x + 8) (x + 7)

Expand

(x + 8) (x + 7) : x^{2} + 15 x + 56

90 = x^{2} + 15 x + 56

Switch sides

x^{2} + 15 x + 56 = 90

Move

90

to the left side

x^{2} + 15 x - 34 = 0

Solve with the quadratic formula

x_{1, 2} = \frac{- 15 \pm 1 5 ^{2} - 4 \cdot 1 \cdot ( - 34 )}{2 \cdot 1}

1 5^{2} - 4 \cdot 1 \cdot (- 34) = 19

x_{1, 2} = \frac{- 15 \pm 19}{2 \cdot 1}

Separate the solutions

x_{1} = \frac{- 15 + 19}{2 \cdot 1}, x_{2} = \frac{- 15 - 19}{2 \cdot 1}

x = \frac{- 15 + 19}{2 \cdot 1} : 2

x = \frac{- 15 - 19}{2 \cdot 1} : - 17

The solutions to the quadratic equation are:

x = 2, x = - 17

x^{2} + 4 x = - 10

x^{2} - 5 x - 100 = 0

- 2 x^{2} - 24 x + 568 = 0

2 y^{2} - 5 y - 12 = 0

2 x^{2} + 3 x = 27

What are the solutions to the equation 90=(x+8)(x+7) ?
The solutions to the equation 90=(x+8)(x+7) are x=2,x=-17
Find the zeros of 90=(x+8)(x+7)
The zeros of 90=(x+8)(x+7) are x=2,x=-17