Answer:
Su=10
Explaination:
So from s to u on the nunebr line is worth 2x-12. So what is s to u worth? Well. S to t on the number line = x-7. T to u =6. And 2 x is worth 12 more than s to u, using th e expression. X has to be at least 8 because otherwise the x-7 wouldn't work, and u might get s to u = 0 or a negative number.
Say x was 13, then 13 - 7 =6. So S to t =6. And r to u =6. So s to u =12. (6+6). Then check if the expression fits this answer of 12. 2x - 12. 2x = 26. 26-12=14, which doesn't match.
Let's try 14. 14-7=7. Then s to u = 7+6=13. The expression: 2x= 28. 28-12=16. 13 and 16 dont match. So we have got further away from what we need. Why don't we try going in the opposite direction. Rather than testing 13 and +1, let's now - 1 and try 12.
If x=12, then s to t =12-7=5. And s to u =6+5=11. The expression: 2x=24.-12=12. We are very close now with 11 and 12.
Lets test x=11!
S to t = 11-7=4. 4+6=10. So s to u =10.
2x=22. 22-12=10. So the expression works and the number line measurements.
The answer is su=10 and x=11.