What is x?

1. X-4=9
2. X-12=21
3. 32=X-13
4. X-12=17
5. -6+x=19
6. X-7=92
7. X-5,5=12
8. 33=x-35

Twice the sum of a number and 4 is equal to three times the difference of the number and 7. find the number.

5x−4≥12 or 12x+5≤−4 can you with this problem

Find the volume of the solid obtained by rotating the region enclosed by the curves y=1x and y=7^-x about the x-axis. (use symbolic notation and fractions where needed.) volume =