Verified Answer :

Substitute:-

3 + 10 + 10 + 17 + 10 =
 
Solve:-

3 + 10 + 10 + 17 + 10 = 50

To answer this we will first substitute for each variable and den solve. lets do it:-

x + y + y + 17 + y = ? 

y = 10

x + 10 + 10 + 17 + 10 =  

x = 3

3 + y + + y + 17 + y = ?

Now lets write it out:-

3 + 10 + 10 + 17 + 10 = ?

Now lets solve step by step:-

3 + 10 = 13 
13 + 10 = 23
23 + 17 = 40
40 + 10 = 50

So, 3 + 10 + 10 + 17 + 10 (x + y + y + 17 + y) =  50

Hope I helped ya!! xD