Apopular extreme sport is artificial wall climbing. a climber is resting at a height of 15 feet while on a climbing tower. if this is 30% of the towers total height find the height of the tower

Let x be the height of the tower. This tower height represents 100% of the height while 15 ft height represents 30% (as indicated in the question).

This is a question of proportionality. That is;

15 ft 30%
x   ft 100%

Therefore,
x*30 = 15*100
x = (15*100)/30 = 50 ft

The height of the tower is 50 ft.

The x's cancel eachother out, so then you do -y+2y=8-y=42y+4y=8