Assertion (A): The graph of 2x = 1 is a line parallel to y-axis.

Reason (R): The equations of the form x = ± k are always parallel to y-axis.

1. A is true, R is false.
2. A is false, R is true.
3. Both A and R are true.
4. Both A and R are false.

Assertion (A): For the equation 4y - 7x + 28 = 0, the value of a is -8.

Reason (R):

4y - 7x + 28 = 0
⇒ 4y + 49 + 28 = 0
⇒ y = $\dfrac{-77}{4}$ i.e. a = $-\dfrac{77}{4}$

1. A is true, R is false.
2. A is false, R is true.
3. Both A and R are true.
4. Both A and R are false.

Assertion (A): If A = (2x, y), B = (x, 2y) and AB = 5 unit, then x + y = 5.

Reason (R):

AB = 5 ⇒ $\sqrt{(2x - x)^2 + (y - 2y)^2}$ = 5
⇒ x² - y² = 25

1. A is true, R is false.
2. A is false, R is true.
3. Both A and R are true.
4. Both A and R are false.

Assertion (A): The distance between the point A(x, 2x) and point B(x, 0) is 4 units, then point B = (2, 0).

Reason (R):

$\sqrt{(x - x)^2 + (2x - 0)^2}$ = 4
⇒ x² = 4 and x = ± 2
∴ B = (2, 0) or (-2, 0)

1. A is true, R is false.
2. A is false, R is true.
3. Both A and R are true.
4. Both A and R are false.