Question

write a two-column proof
Given 7y=8x-14;y=6
Prove x=7
Where do I start?

Answer 1

7y = 8x-14 given
7*6 = 8x-14 substitution
42 = 8x-14
42+14 = 8x equality of addition
56 = 8x
7 = x division equality

Answer 2

Thank you so much @anonymos