The first term of an arithmetic sequence is 1. The first, second and fifth terms of the arithmetic sequence form a geometric sequence. The common difference is not zero. Find the common difference of the arithmetic sequence.​

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

The clayton family’s pool has vertices at the coordinates (0, 2), (0, 5), (2, 5), (2, 6), (5, 6), (5, 1), (2, 1), and (2, 2). if each grid square has an area of 9 square feet, what is the area of the pool?

Ineed with angles and the measure of them i have abc a is 65 and b is (3x-10) and c is (2x) find the value of x