Question

kathi starts with a number. she adds 3 to her number, then doubles the result. finally, she subtracts 7. if she ended with 9 what number did ahe start with

Answer 1

An equation is:
2(x+3)-7=9
Distribute the 2
2(x)+2(3) -7=9
2x+6-7=9
Combine like terms
2x-1=9
Add one to both sides
2x-1+1=9+1
2x=10
Divide both sides by two to isolate the variable.
2x/2=10/2
x=m

Answer 2

I say

5+3=8
8+8=16
16-7=9