The value of x varies directly with y and when x = 1/4y = 2

How many solutions does the nonlinear system of equations graphed bellow have?

What is the solution to the equation below? 3/x-2+6=square root x-2 +8

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?