Question

Q13. The equation of straight line passing
through the point (1, 2) and parallel to
the line y = 3x + 1 is
(A) y + 2 = x + 1
(B) y + 2 = 3 (x + 1)
(C) Y- 2 = 3 (x - 1)
(D) y-2 = x - 1​

Answer 1

answer:

y=3x−1

General equation of line is y=mx+c

∴m=3

If two lines are perpendicular, thenm

1

⋅m

2

=−1

Slope of line perpendicular to y=3x−1 will be

3

−1

∴ Equation of line y=

3

−1

x+c

3y+x=c

This line passes through the point (1,2)

∴3(2)+1=c

c=7

Equation of line becomes

x+3y=7

x+3y−7=0