Well, to find the perimeter we have to add all of the side lengths, so let's do that:
2x+3 +2x+3 +2x
And we know that this equals 36 so let's solve for x
2x+3+2x+3+2x = 36
6x+6 = 36
6x = 30
x = 5
So we know know that x = 5.
Now all you have to do is plug in the values of x into the lengths
2(5) + 3
= 10+3
= 13 is the length of two of the sides.
2x
= 2(5)
= 10
And 10 is the length of the last side.
4+3 = 7
This is the amount of dollars spent each day
25/7 = 3 4/7
This means the money will last for 3 days.