House 1 has 6 sticks. House 2 has 11, house 3 has 16, and the pattern goes on. Each following house uses 5 more sticks. At design 17, we can use this pattern to solve for it. We would do 5*17, remembering to add 1 as house 1 has its own additional stick. 5*17 + 1 = 86
Hope this helps, let me know if you have any questions :))
