Write an equation that could be used to find the measure of each angle

Classify the following triangle check all that apply

Find the roots of the equation below. x^2 - 6 + 9 = 0

The distribution of the amount of money spent by students for textbooks in a semester is approximately normal in shape with a mean of $235 and a standard deviation of $20. according to the standard deviation rule, how much did almost all (99.7%) of the students spend on textbooks in a semester?