What are the solutions to the equation (n(n-3))/2-n=25 ?

The solutions to the equation (n(n-3))/2-n=25 are n=10,n=-5

Find the zeros of (n(n-3))/2-n=25

The zeros of (n(n-3))/2-n=25 are n=10,n=-5

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

Popular >

\frac{n ( n - 3 )}{2} - n = 25

n = 10, n = - 5

Solution steps

\frac{n ( n - 3 )}{2} - n = 25

Multiply both sides by

2

n (n - 3) - 2 n = 50

Expand

n (n - 3) - 2 n : n^{2} - 5 n

n^{2} - 5 n = 50

Move

50

to the left side

n^{2} - 5 n - 50 = 0

Solve with the quadratic formula

n_{1, 2} = \frac{- ( - 5 ) \pm ( - 5 ) ^{2} - 4 \cdot 1 \cdot ( - 50 )}{2 \cdot 1}

(- 5)^{2} - 4 \cdot 1 \cdot (- 50) = 15

n_{1, 2} = \frac{- ( - 5 ) \pm 15}{2 \cdot 1}

Separate the solutions

n_{1} = \frac{- ( - 5 ) + 15}{2 \cdot 1}, n_{2} = \frac{- ( - 5 ) - 15}{2 \cdot 1}

n = \frac{- ( - 5 ) + 15}{2 \cdot 1} : 10

n = \frac{- ( - 5 ) - 15}{2 \cdot 1} : - 5

The solutions to the quadratic equation are:

n = 10, n = - 5

(5 p + 1)^{2} = 12

81 x^{2} = 169

r^{2} - 3 r = 0

9 a^{2} = 81

- x^{2} - 2 x + 4 = 2 - 2 x

What are the solutions to the equation (n(n-3))/2-n=25 ?
The solutions to the equation (n(n-3))/2-n=25 are n=10,n=-5
Find the zeros of (n(n-3))/2-n=25
The zeros of (n(n-3))/2-n=25 are n=10,n=-5