SOLUTION: 2nSquared-7n-3=0 I dont know how to do this and I need help..So please help.

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: 2nSquared-7n-3=0 I dont know how to do this and I need help..So please help.      Log On


   

Question 667: 2nSquared-7n-3=0
I dont know how to do this and I need help..So please help.
Answer by janinecb(25) About Me  (Show Source):
You can put this solution on YOUR website!
This equation doesn't factor, so the quadratic formula is probably the best choice for how to solve it.
The quadratic formula is:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
This formula assumes you know that the equation needs to be in
the form of ax%5E2+%2B+bx+%2B+c+=+0.
For your equation:
a = 2
b = -7
c = -3
So, when you plug in the a, b and c, you get:
n+=+%28-2+%2B-+sqrt%28%28-7%29%5E2-4%2A2%2A%28-3%29%29%29%2F%282%2A2%29
When you simplify the information under the square root and in the denominator, you get:
n+=+%28-2+%2B-+sqrt%2849%2B24%29%29%2F%284%29
Then:
n+=+%28-2+%2B-+sqrt%2875%29%29%2F%284%29
Then simplify the square root. sqrt%2875%29=sqrt%2825%29%2Asqrt%283%29=5+sqrt%283%29
This leaves you with:
n+=+%28-2+%2B-+5+sqrt%283%29%29%2F%284%29
This can be your final two answers, unless it needs to be in decimal form and that requires a calculator or square root table.