Question

1. The equation of a line parallel to the y-axis and passing through (3, 1) is y = 1.
2. The equation of a line with slope −3 and y-intercept 3 is 3x + y = 3.

Options

• Only (i)

• Only (ii)

• Both (i) and (ii)

• Neither (i) nor (ii)

Answer 1

Only (ii)

Explanation:

⇒ Going through (i) statement,

• A line parallel to the y-axis is vertical.
• The equation for a vertical line is always x = constant.
• Since the point is (3, 1), the correct equation is x = 3.

So, the statement is invalid.

⇒ Going through (ii) statement,

Using the slope-intercept form y = mx + c

• Slope (m) = −3
• y-intercept (c) = 3

Equation:

y = −3x + 3

Rearrange it,

3x + y = 3

So, the statement is valid.