What are the solutions to the equation x(x+1)=420 ?

The solutions to the equation x(x+1)=420 are x=20,x=-21

Find the zeros of x(x+1)=420

The zeros of x(x+1)=420 are x=20,x=-21

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x (x + 1) = 420

x = 20, x = - 21

Solution steps

x (x + 1) = 420

Expand

x (x + 1) : x^{2} + x

x^{2} + x = 420

Move

420

to the left side

x^{2} + x - 420 = 0

Solve with the quadratic formula

x_{1, 2} = \frac{- 1 \pm 1 ^{2} - 4 \cdot 1 \cdot ( - 420 )}{2 \cdot 1}

1^{2} - 4 \cdot 1 \cdot (- 420) = 41

x_{1, 2} = \frac{- 1 \pm 41}{2 \cdot 1}

Separate the solutions

x_{1} = \frac{- 1 + 41}{2 \cdot 1}, x_{2} = \frac{- 1 - 41}{2 \cdot 1}

x = \frac{- 1 + 41}{2 \cdot 1} : 20

x = \frac{- 1 - 41}{2 \cdot 1} : - 21

The solutions to the quadratic equation are:

x = 20, x = - 21

∣ 2 - 3 x ∣ = 5

16 x^{4} + 8 x^{2} - 3

(x - 4)^{2} = 2 x^{2} - 15 + 22

- 5 ∣ - 3 x + 2 ∣ - 2 = - 2

867

What are the solutions to the equation x(x+1)=420 ?
The solutions to the equation x(x+1)=420 are x=20,x=-21
Find the zeros of x(x+1)=420
The zeros of x(x+1)=420 are x=20,x=-21