Question

There are 32 red or blue marbles in a bag. The number of red marbles is 4 more than 3 times the number of blue marbles. Write and solve a system of linear equations. How many red marbles are in the bag? How many blue marbles are in the bag?

Answer 1

# red marbles = 25

# blue marbles = 7

Explanation:

r + b = 32

r = 4 + 3b

substitute '4 + 3b' for 'r' in the 1st equation

4 + 3b + b = 32

4 + 4b = 32

4b = 28

b = 7

red = 32 - 7

r = 25