Question

What is the equation of a line that contains the point (2.1) and is parallel to

the line: y = 3x - 4?
A. y--x-
B. y--x-4
C. y= 3x-4
D. y= 3x - 5

Answer 1

D

Answer: the answer is (D)

Answer 2

D

Explanation:

The equation of a line in slope- intercept form is

y = mx + c ( m is the slope and c the y- intercept )

y = 3x - 4 ← is in slope- intercept form

with slope m = 3

Parallel lines have equal slopes , so

y = 3x + c ← is the partial equation

To find c substitute (2, 1) into the partial equation

1 = 6 + c ⇒ c = 1 - 6 = - 5

y = 3x - 5 ← equation of parallel line → D