We are going to start with the sum of x and 3. You can write that like this : x+3. Then, it says “triple the sum of x and 3”. That would be 3(x+3). Then it says “four fewer”. So that is 3(x+3)-4. And all of that equals to 17. So the equation is 3(x+3)-4=17.
Then to solve that, we are going to add 4 to both sides. So now our equation looks like 3(x+3)=21. Then divide by 3 on both sides. (x+3)=7. Subtract 3 on both sides. x=4.