Which are the solutions of x2 = -7x - 8? O 7\2 - 17\4, -7\2 + 17\4 O -7\2 -17\4, -7\2 + 17\4 O 7 - 17\2, -7 + 17\2 O -7 - 17, -7 + 17\2​

Sum of the interior angles of a pentagon

36x2 + 49y2 = 1,764 the foci are located at: (-√13, 0) and (√13,0) (0, -√13) and (0,√13) (-1, 0) and (1, 0)edit: the answer is (- the square root of 13, 0) and (the square root of 13, 0)

Arandom sample of n = 25 observations is taken from a n(µ, σ ) population. a 95% confidence interval for µ was calculated to be (42.16, 57.84). the researcher feels that this interval is too wide. you want to reduce the interval to a width at most 12 units. a) for a confidence level of 95%, calculate the smallest sample size needed. b) for a sample size fixed at n = 25, calculate the largest confidence level 100(1 − α)% needed.