Question

4x^2+16x-9=0
please help

Answer 1

x = 5.071 and 9.071

Explanation:

So there is some good news here, all of these numbers are a perfect square so it is going to make solving this a lot nicer, so to solve you can call the 4 a, the 16 b and the -9 c and this can be plugged into the quadratic formula. Which is -b±
`\frac{\sqrt{b^(2) -4ac } }{2a}`, which looks scary, but now all that needs to be done is plugging in numbers which would look like so:

-16±
`\frac{\sqrt{16^(2)-4(4)(-9) } }{2(4)}`

This equation can now be simplified to look more like this:

-16±
`(√(256- (-144)) )/(8)`

This then can be broken down even more to:

-16±
`(√(400) )/(8)`

And since all of these numbers are divisible by 8, this can be simplified even more:

-2±
`√(50)`

And since we are going to add and subtract 2 from the square root of 50 we will have 2 answers.

The square root of 50 is 7.071

If you add 2, its 5.071

if you subtract 2 it 9.071

So your 2 answers are 5.071 and 9.071