If a varies directly as b, and a=16 when b=4, find the equation that relates a and b.

if a varies directly as b and a=16 when b=4 i think that u can add or multiply

a = 4b

Step-by-step explanation:

Given that a varies directly as b then the equation relating them is

a = kb ← k is the constant of variation

To find k use the condition a = 16 when b = 4, that is

16 = 4k (divide both sides by 4)

4 = k, thus

a = 4b ← equation of variation