Question

The sum of the roots of 8x² - 2x = 1 is:
-1/4
1/4
-1/8

Answer 1

8x^2 - 2x = 1
8x^2 - 2x - 1 = 0

(2 +/-√(-2)^2 - 4(8)(-1))/ 2(8)
(2 +/-√4 + 32) / 16
(2 +/-√36) / 16
(2 +/- 6) / 16

2+6/16
1/2

2-6/16
-1/4

now since they want the sum of the roots
1/2 - 1/4

sum = 1/4

Answer 2

8x^2-2x-1=0

8x^2-4x+2x-1=0

4x(2x-1)+1(2x-1)=0

(4x+1)(2x-1)=0

x=1/2 and -1/4

So the sum is 1/2-1/4=1/4

1/4