Step-by-step explanation:

First subtract 4 from both sides

then simplify

add -5 to both sides

since a variable shouldn't be negative the answer should be

(I prefer having the variable on the left side)
Answer:
There are 3 red marbles.
Step-by-step explanation:
The ratio of red marbles to blue marbles is 3:2, so for every two blue marbles there are three red marbles. This means that there are three red marbles for every four marbles in the bag. Therefore, if there are five marbles in the bag, there must be three red marbles and two blue marbles.