Question

Y is directly proportional to (x-4) when x=16, y=3 find y in terms of x

Answer 1

y = x/4 - 1

Step by step explanation in pic

Answer 2

y = ¼(x-4)

Explanation:

Before solving the question, let's look at one example,

• A is directly proportional to B means A∝B which also means A=kB where k is a constant.

In this case, y is directly proportional to (x-4) means that y∝(x-4) which can also mean that y=k(x-4).

Hence, to find the value of k, substitute x=16, y=3 into y=k(x-4),

3=k(16-4)

k=3/12

k=1/4

After that, substitute the k value into the equation,

y = ¼(x-4)