Soren solves the quadratic equation x^2 + 8x – 9 = 0 using the quadratic formula. In which step did Soren make an error?

Answer for 10 points show work you guys in advanced < 3

List x1, x2, x3, x4 where xi is the left endpoint of the four equal intervals used to estimate the area under the curve of f(x) between x = 4 and x = 6. a 4, 4.5, 5, 5.5 b 4.5, 5, 5.5, 6 c 4.25, 4.75, 5.25, 5.75 d 4, 4.2, 5.4, 6

Solve this problem! extra ! 3025/5.5 = a/90.75