Correct Answer - Option 2 : 3

**Concept:**

If x ∈ R then we express it by writing xRy and say that " x is related to y with relation R"

Thus, (x, y) ∈ R ⇔ xRy

**Calculation:**

Given

2x + 3y = 20

The relation R can be written as

R = {(1,6), (4, 4), (7, 2)}

There are 3 elements in the form (x, y) are there in R.