# Solve 3

(6n+1) (4n-1) = 3n2

Result

n1 =  0.271
n2 =  -0.176

#### Solution:

$\ \\ 21n^2 -2n -1=0 \ \\ \ \\ a=21; b=-2; c=-1 \ \\ D=b^2 - 4ac=2^2 - 4\cdot 21 \cdot (-1)=88 \ \\ D>0 \ \\ \ \\ n_{1,2}=\dfrac{ -b \pm \sqrt{ D } }{ 2a }=\dfrac{ 2 \pm \sqrt{ 88 } }{ 42 }=\dfrac{ 2 \pm 2 \sqrt{ 22 } }{ 42 } \ \\ n_{1,2}=0.04761905 \pm 0.22335313142016 \ \\ n_{1}=0.27097217903921 \ \\ n_{2}=-0.17573408380112 \ \\ \ \\ \text{ Factored form of the equation: } \ \\ 21 (n -0.27097217903921) (n +0.17573408380112)=0 \ \\ \ \\ n_{1}=0.271 \doteq 0.271=0.271$

Checkout calculation with our calculator of quadratic equations.

$n_{2}=(-0.1757) \doteq -0.1757=-0.176$

Our examples were largely sent or created by pupils and students themselves. Therefore, we would be pleased if you could send us any errors you found, spelling mistakes, or rephasing the example. Thank you!

Leave us a comment of this math problem and its solution (i.e. if it is still somewhat unclear...):

Be the first to comment!

Tips to related online calculators
Looking for help with calculating roots of a quadratic equation?
Do you have a linear equation or system of equations and looking for its solution? Or do you have quadratic equation?

## Next similar math problems:

1. Reciprocal equation 2
Solve this equation: x + 5/x - 6 = 4/11
2. Variation equation
Solve combinatorics equation: V(2, x+8)=72
3. Discriminant
Determine the discriminant of the equation: ?
Find the roots of the quadratic equation: 3x2-4x + (-4) = 0.
5. Equation
Equation ? has one root x1 = 8. Determine the coefficient b and the second root x2.
6. Roots
Determine the quadratic equation absolute coefficient q, that the equation has a real double root and the root x calculate: ?
7. Cinema 4
In cinema are 1656 seats and in the last row are 105 seats , in each next row 3 seats less. How many are the total rows in cinema?
8. Equation 23
Find value of unknown x in equation: x+3/x+1=5 (problem finding x)
If 5x + x² > 100, then x is not
Quadratic equation ? has roots x1 = -26 and x2 = -86. Calculate the coefficients b and c.
11. The product
The product of a number plus that number and its inverse is two and one-half. What is the inverse of this number
12. Variable
Find variable P: PP plus P x P plus P = 160
13. Tubes
Iron tubes in the warehouse are stored in layers so that each tube top layer fit into the gaps of the lower layer. How many layers are needed to deposit 100 tubes if top layer has 9 tubes? How many tubes are in bottom layer of tubes?
14. Equation with abs value
How many solutions has the equation ? in the real numbers?
15. Square root 2
If the square root of 3m2 +22 and -x = 0, and x=7, what is m?
16. Evaluation of expressions
If a2-3a+1=0, find (i)a2+1/a2 (ii) a3+1/a3
17. Theorem prove
We want to prove the sentence: If the natural number n is divisible by six, then n is divisible by three. From what assumption we started?