The base of an isosceles triangle is 15mm long and the altitude is 8mm. What is the length of the legs of the triangle? Round your answer to the nearest tenth.

Afarmer has a large field that is x feet in length. he wants to fence in a rectangular section in the middle of the field , leaving a length of 100 feet of open field behind each end of the fenced rectangle.he also wants the width of the fenced-in space to be 100 feet less than its length. find the expressions to represent the length and width of the fenced section of the field