How is a net useful when finding the surface area of prisms and pyramids

4. find the geometric mean of 4 and 12. 24 8

What number should be added to both sides of the equation to complete this square? x^2-10x=7

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78. for an 10 month period, the last term is and the series sum is . for a 15 month period, the last term is and the series sum is . for a 20 month period, the last term is and the series sum is