Adog's weight increased by 50% in 3 years. by the end of 3 years, the dog weighed 45 pounds. how much did the dog weigh 3 years ago?

Element x decays radioactively with a half life of 8 minutes. if there are 450 grams of element x, how long, to the nearest tenth of a minute, would it take the element to decay to 37 grams?

Atriangular bandana has an area of 46 square inches. the height of the triangle is 5 3 4 inches. enter and solve an equation to find the length of the base of the triangle. use b to represent the length of the base.

Need ! give step by step solutions on how to solve number one [tex]\frac{9-2\sqrt{3} }{12+\sqrt{3} }[/tex] number two [tex]x+4=\sqrt{13x-20}[/tex] number three (domain and range) [tex]f(x)=2\sqrt[3]{x} +1[/tex]