Q:

Use the quadratic formula to solve the equation. If necessary, round to the nearest hundredth. –2y2 + 6y = –2–0.61, 6.61–0.3, 3.3–3.3, 0.3–11.5, 14.5

Accepted Solution

A:
For this case we have the following equation:
 -2y2 + 6y = -2
 Rewriting we have:
 -2y2 + 6y + 2 = 0
 Using the quadratic formula we have:
 x = (- b +/- root (b ^ 2 - 4 * a * c)) / (2 * a)
 Substituting values:
 x = (- (6) +/- root ((6) ^ 2 - 4 * (- 2) * (2))) / (2 * (- 2))
 Rewriting:
 x = (- 6 +/- root (36 + 16)) / (- 4)
 x = (- 6 +/- root (52)) / (- 4)
 x = (- 6 +/- root (4 * 13)) / (- 4)
 x = (- 6 +/- 2 * root (13)) / (- 4)
 x = (- 3 +/- root (13)) / (- 2)
 The roots are:
 x1 = (- 3 - root (13)) / (- 2)
 x2 = (- 3 + root (13)) / (- 2)
 Rewriting:
 x1 = -0.3
 x2 = 3.3
 Answer:
 –0.3, 3.3