Add all the numbers of the triangle and then divide them by the sides
1. Distribute
5(2n-4)
10n-20
9(n+2)
9n+18
10n-20=9n+18
2. Combine like terms
combine the terms with “n”, and then combine the other numbers.
Hope this helps!
To find the area of a polygon you have to write the formula of it which is area= 1/2 x perimeter x apothem . hope this helps