The purpose of solving an algebraic expression in an equation is to find the unknown variable. When two expressions are equated, they form an equation and therefore, it becomes easier to solve for the unknown terms. To solve an equation, place the variables on one side and the constants on the other side.
Sure hope this helps
To find the answer, use 
, and then use the equation 
To find it's half life.
Answer: Canada Vegetation
Forests are primarily mixes of white and black spruce, lodgepole pine, balsam poplar, paper birch and trembling aspen. Common understorey plants include mountain and green alders, highbush cranberry, wild rose, Canadian buffalo berry and reed grass, fireweed, lingonberry, twinflower and feather mosses.
Answer:
For number 3 the answer is -4
