The opposite of a nonzero integer is the inverse of it. So to get the opposite, change the sign.
For example:
What's the opposite of 3?
-3.
I hope that I explained well :)
1 triangle: 2*6 + 1*5
2 triangles: 2*6 + 2*5
3 triangles: 2*6 + 3*5
So for n triangles: p = 2*6 + n*5 = 12 + 5n
1.625 rounded to the nearest hundredth is 1.63
if you make a graph and add the coordinates on the graph you can use that find out how it creates a ratio of 1:2
