-2x +4=8x-6 equations/inequalities

Wrote and expression for the difference of p and 4

The angle of elevation from point a to the top of the cliff is 38 degrees. if point a is 80 feet from the base of the cliff , how high is the cliff ?

Situation: an archaelogist in turkey discovers a spear head that contains 54% of its original amount of c-14. n = noekt no = inital amount of c-14 (at time t = 0) n = amount of c-14 at time t k = 0.0001 t = time, in years find the age of the spear head to the nearest year