Solve the following system of equations by the substitution method.

8x = 2y + 5
3x = y + 7

what is the solution set?

{(-41/2, -9/2)}
{(-9/2, -41/2)}
∅

The blue whale is the largest animal living on the earth. the average blue whale measures 100 feet long (30 meters) and weighs 300,000 pounds (136,000 kilograms). a whale’s head is 1⁄3 of the length of its body. a new baby whale is 1⁄4 the length of a grown whale. the average man is 1⁄17 the length of a blue whale, and 1⁄1,818 its weight. a human baby measures 1⁄4 of the length of an adult. calculate the following information: how long is a whale’s head? how long is a new baby whale? how tall is the average man? how much does the average man weigh? how tall is the average human baby?

You love to play soccer! you make a shot at the net 8 times during a game! of those 8 attempts, you score twice. what percent of the time did you score?

Mrs. gehrke said cheddar weighs 16.8 pounds. he actually weighs 15.2 pounds. what is the percent error?