SOLUTION: 2x*-3x-4 x= -3

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Question 77582This question is from textbook BEGINNING ALGEBRA
: 2x*-3x-4 x= -3 This question is from textbook BEGINNING ALGEBRA

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
%282x%29%28-3x%29-4x=-3

-6x%5E2-4x=-3 Multiply

-6x%5E2-4x%2B3=0 Add 3 to both sides

6x%5E2%2B4x-3=0 Factor out a negative 1
Now use the quadratic formula to solve for x:
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 6x%5E2%2B4x%2B-3+=+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=%284%29%5E2-4%2A6%2A-3=88.

Discriminant d=88 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-4%2B-sqrt%28+88+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%284%29%2Bsqrt%28+88+%29%29%2F2%5C6+=+0.448402626637238
x%5B2%5D+=+%28-%284%29-sqrt%28+88+%29%29%2F2%5C6+=+-1.11506929330391

Quadratic expression 6x%5E2%2B4x%2B-3 can be factored:
6x%5E2%2B4x%2B-3+=+6%28x-0.448402626637238%29%2A%28x--1.11506929330391%29
Again, the answer is: 0.448402626637238, -1.11506929330391. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+6%2Ax%5E2%2B4%2Ax%2B-3+%29