The cost of a pen is 3 times the cost of a pencil. The total cost of 8 pencils and 5 pens is $11.50. Please help me to find the costs of a pen and a pencil.

The length of triangle base is 26. a line, which is parallel to the base divides the triangle into two equal area parts. find the length of the segment between triangle legs.

Which of the points a(6, 2), b(0, 0), c(3, 2), d(−12, 8), e(−12, −8) belong to the graph of direct variation y= 2/3 x?

If value of cos330° is √3/2 then find tan165°.