Answer:
Blue marbles: 18
Green marbles: 25
Step-by-step explanation:
First off, we have to define our variables.
g = # of green marbles
b = # of blue marbles
We know two equations:
g + b = 43 and g = b + 7
If you're wondering how I got the first equation, it was because the number of green and blue marbles is 43. For the second equation, we know that there are 7 more green marbles than blue marbles.
Now, we have an equation for the number of green marbles. We can plug that equation into the equation g + b = 43.
So, (b + 7) + b = 43.
When we simplify it, we get 2b + 7 = 43.
We subtract 7 from both sides, which gets us 2b = 36.
Now, b = 36/2.
b = 18.
So, we found out the number of blue marbles that we have. We know that g + b = 43. Now, all we have to do is plug in the number of blue marbles into that equation to find out the number of green marbles.
g + 18 = 43.
g = 43 - 18.
g = 25.
Thus, the number of green marbles we have is 25 and the number of blue marbles is 18.