The common denominator would be 18. So, 5/6 becomes 15/18 and 7/9 becomes 14/18
X = sqrt(5^2 - 3^2) = 4
y = sqrt(7^2 - 3^2) = sqrt 40
Horizontal distance = x + y + 3 = 7 + sqrt40
1+3+5+7+...+999 =
= 1+2+3+4+...+500
+1+2+3+...+499
= 2·(1+2+3+...+499) + 500
= 2·(499·500)/2 + 500
= 499·500 + 500
= 500·(499 + 1)
= 500·500
= 250.000
