Answer:
I think 120
Step-by-step explanation:
If you look at the model RM is the same length as PM. PM=10 so RM=10.
It is given in the question that
Ms. Velez will use both x gray bricks and y red bricks to build a wall around her garden. Gray bricks cost $0.45 each and red bricks cost $0.58 each. She can spend up to $200 on her project, and wants the number of red bricks to be less than half the number of gray bricks.
Maximum she can spend is $200. That is

And

And that's the required inequalities .
3^2+3^2=c^2
18=c^2
c=3sqrt2
Or 4.24 if you need a decimal answer