Question

1.What values of a,b,and c would you use in the quadratic formula for the following equation?

Answer 1

First, rearrange the quadratic equation:
5x² + 9x - 4 = 0

Now, compare it to the general quadratic equation:
ax² + bx + c = 0

Therefore you get:
a = +5
b = +9
c = -4

And the quadratic formula will be:

x = [-b +/- √(b² - 4ac)] / 2a
   = [ -5 +/- √(81 - 4·5·(-4))] / 2·5
   = (-5 +/- √161) / 10