Question

Find the sum of the roots of the quadratic x^2 + 7x - 13 = 0

Answer 1

-7

Explanation:

You use the quadratic formula of
`ax^(2) +bx+c = 0` to get:

a = 1

b = 7

c = -13

then you plug that into x= (-b ± √b²-4ac)/(2a) :

x= ( -7 ± √7²- 4(1)(-13) )/(2(1))

`x=-(7)/(2) + (√(101))/(2) \\\\x=-(7)/(2) - (√(101))/(2)`

The sum of these two x values turns out to be:

`x=-(7)/(2) + (√(101))/(2)+( -(7)/(2) - (√(101))/(2) )= -(14)/(2) = 7`