A 10-ft ladder leans against the side of a house. The bottom of the latter is 5 ft from the side of the house. How high is the top of the ladder from the ground. If necessary, round your answer to the nearest tenth. PLEASE HELP

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