SOLUTION: what is the best way to solve 3xsquared+2x-4=0 and then solve my email is shemkajacob@gmail.com

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Question 273564: what is the best way to solve 3xsquared+2x-4=0 and then solve my email is shemkajacob@gmail.com
Found 2 solutions by edjones, mananth:
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
3x^2+2x-4=0
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 3x%5E2%2B2x%2B-4+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%282%29%5E2-4%2A3%2A-4=52.

Discriminant d=52 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-2%2B-sqrt%28+52+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%282%29%2Bsqrt%28+52+%29%29%2F2%5C3+=+0.86851709182133
x%5B2%5D+=+%28-%282%29-sqrt%28+52+%29%29%2F2%5C3+=+-1.535183758488

Quadratic expression 3x%5E2%2B2x%2B-4 can be factored:
3x%5E2%2B2x%2B-4+=+3%28x-0.86851709182133%29%2A%28x--1.535183758488%29
Again, the answer is: 0.86851709182133, -1.535183758488. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+3%2Ax%5E2%2B2%2Ax%2B-4+%29

.
Ed

Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
what is the best way to solve 3xsquared+2x-4=0 and then solve my email is shemkajacob@gmail.com
3x^2+2x-4
this is of the form ax^2 + bx +c
So a= 3 , b =2, c=-4
the roots of the equation are given by
x1,x2 = -b +/- sqrt(b^2-4ac) / 2a
x1= - 2 + sqrt( 4-4*3*-4)
= -2 + sqrt(4+48) / 6
= -2 +sqrt52 / 6
= -2 + 7.21 /6
= +5.21/6
= 0.868


x2= -b - sqrt(b^2-4ac) / 2a
== -2 -sqrt(4+48) / 6
= -2 -sqrt52 / 6
= -2-7.21 /6
= - 9.21/6
=-1.535