How do you solve $7x^2 + 8x + 5 = 0$ using the quadratic formula?

Question

3401 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-03-08T11:02:10

$x= (-8+-2sqrt(-19))/14$

The quadratic formula states that the solutions to a quadratic of the form $ax^2 +bx+c = 0$ are given by

$x =( -b+-sqrt(b^2-4ac))/(2a)$

So in this case

$x = (-8+-sqrt(8^2-4*7*5))/(2*7)$

$=(-8+-sqrt(64-140))/14 = (-8+-sqrt(-76))/14 = (-8+-2sqrt(-19))/14$

This has only imaginary solutions.

How do you solve 7x^2 + 8x + 5 = 07x^2 + 8x + 5 = 0 using the quadratic formula?