Solve the proportion
17/3 = y/6

To solve a proportion, you can either use cross products or basic multiplication.

To do cross products, you would multiply 17 (1st numerator) by 6 (2nd denominator). 

Do the same with the other diagonal angle, 3 times y.

You'll end up with 3y = 102.

To solve for y, you divide both sides by 3.

102 ÷ 3 = 34

y = 34

The other way you could solve this is to see that 6 is 2 times as large as 3, so you would multiply 17 by 2 to get an equal proportion.

3 × 2 = 6
17 × 2 = 34

Your final answer is y = 34. Hope this helps! :)