SOLUTION: how would i do the problem 3x^2+4x=7

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Question 115031: how would i do the problem 3x^2+4x=7
Found 2 solutions by MathLover1, jim_thompson5910:
Answer by MathLover1(20850) (Show Source):
You can put this solution on YOUR website!

��. Write it in the standard form

��.use quadratic formula to solve

��.divide by

Answer by jim_thompson5910(35256) (Show Source):
You can put this solution on YOUR website!
Start with the given equation

Move all of the terms to the left side

Let's use the quadratic formula to solve for x:

Starting with the general quadratic

the general solution using the quadratic equation is:

So lets solve ( notice , , and )

Plug in a=3, b=4, and c=-7

Square 4 to get 16

Multiply to get

Combine like terms in the radicand (everything under the square root)

Simplify the square root (note: If you need help with simplifying the square root, check out this solver)

Multiply 2 and 3 to get 6

So now the expression breaks down into two parts

or

Lets look at the first part:

Add the terms in the numerator
Divide

So one answer is

Now lets look at the second part:

Subtract the terms in the numerator
Divide

So another answer is

So our solutions are:
or

Notice when we graph , we get:

and we can see that the roots are and . This verifies our answer