A sample of 400 racing cars showed that 80 of them cost over $700,00. What is the 99% confidence interval for the true proportion of racing cars that cost over $700,00?

There is a line with slope 1/a going through the point (a, a²). find the equation of the line perpendicular to this line at this point. (don’t let this problem intimidate you! solve the problem as you would if i’d given you specific values. just use variables instead.)

Solve the system of equations y= 3/2 - 1, -x+ y =-3

What makes a trapezoid an isosceles trapezoid?