We an represent this problem as \(\frac{1}{2}ab = 5(a+b)\), where a and b are the two legs. We can now simplify this equation further.
\(\frac{1}{2}ab = 5a+5b\)
\(ab=10a+10b\)
\(ab-10a-10b=0\)
We can now use Simon's Favourite Factoring Trick to simplify this.
\(ab-10a-10b+100=100\)
\((a-10)(b-10)=100\)
The factor pairs of 100 are (1, 100), (2,50), (4, 25), (5, 20), and (10, 10). We now choose a and b to make thepart in the parentheses equal to one of these pairs. Therefore, all possibilities for the legs (a and b) are (11, 110), (12, 60), (14, 35), (15, 30), and (20, 20). We can calculate the area for each of these.
\(\frac{1}{2}(11)(110)=605\)
\(\frac{1}{2}(12)(60)=360\)
\(\frac{1}{2}(14)(35)=245\)
\(\frac{1}{2}(15)(30)=225\)
\(\frac{1}{2}(20)(20)=200\)
Therefore, the sum of all areas is 605 + 360 + 245 + 225 + 200 = 1635