Use graphing technology to approximate the solutions of the equation. x2 + 6x -9 = x + 6 + 6
Each of the following graphs is shown in a (-20,20,2] by [ -20,20,2] viewing window. Choose the graph that can be used to solve the equation.

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.