Question

The sum of the roots of 2x 2 + 8x - 3 = 0 is

-3/2
3/2
-4
4

Answer 1

-4

Explanation:

From the qquadratic formula

x1 = [ -b +√(b² - 4ac) ] / 2a

x2 = [ -b -√(b² - 4ac) ] / 2a

When added together the ± square root cancels out leaving

(-b/2a) + (-b/2a) = -b/a

For 2x² + 8x -3 = 0

-b/a = -8/2

-b/a = -4