Answer: a = 7b
Explanation:
If a varies directly as b, the the equation representing this relationship is expressed as
a = kb
where
k is the constant of proportionality.
From the information given, when a = 49, b = 7
Substituting a = 49 and b = 7 into the equation, it becomes
49 = 7k
Dividing both sides by 7,
7k/7 = 49/7
k = 7
By substituting k = 7 into the equation, the equation relating a and b is
a = 7b
