Can someone please help me answer this question asap thank you . No links please and thank you.

The angle of a triangle are given as 6x,(x-3), and (3x+7). find x then find the measures of the angles

Prove (a) cosh2(x) − sinh2(x) = 1 and (b) 1 − tanh 2(x) = sech 2(x). solution (a) cosh2(x) − sinh2(x) = ex + e−x 2 2 − 2 = e2x + 2 + e−2x 4 − = 4 = . (b) we start with the identity proved in part (a): cosh2(x) − sinh2(x) = 1. if we divide both sides by cosh2(x), we get 1 − sinh2(x) cosh2(x) = 1 or 1 − tanh 2(x) = .

The perimeter of a rectangular lot of land is 436 ft. this includes an easement of x feet of uniform width inside the lot on which no building can be done. if the buildable area is 122 ft by 60 ft, determine the width of the easement. select one: a. 9 feet b. 18 feet c. 4.5 feet d. 7 feet