Answer:
These equations are equivalent because after you solve the equation the answer are the same. For example 2+2 and 3+1 are equivalent. They both equal four. In these problems are x=3 and x=3.5 they are the same beause of the answer on problem 2 6-x. That makes them both have the same answer
Step-by-step explanation:
7x-9=12
+9=+9
7x=21
/7=/7
x=3
