1.
7x+1=15
2. (7x + 1) + (−1) = 15 + (−1)
3. 7x + [1 + (−1)] = 15 + (−1)
7x+0=15+ (−1)
7x=15+ (-1)
7x = 14
(7x)=(14)
(-½ · 7 ) x = — - (14)
5.
6.
N
8.
9.
10.
1+x=(14)
x=2
1.
?
2. ?
3. ?
4. ?
5. ?
6. Substitution principle
7. ?
8. 2
9.3
10. ?