Question

A line passes through ( 2, -1) and (4,5)
Which answer is the equation of the line ?

A) -3x + y = -7
B) -3x + y = 17
C) -3x + 5y = 13
D) -3x + 5y = -13

Answer 1

Answer:

A) $-3x+y=-7$

Step-by-step explanation:

Slope of the line:

$\frac{5-(-1)}{4-2} =\frac{6}{2} =3$

$y=mx+b$

$y=3x+b$

Plug in x and y values of any of the points.

$5=3(4)+b$

$5=12+b$

$b=-7$

Equation of the line:

$y=3x-7$

Subtract 3x from both sides:

$y-3x=-7$

$-3x+y=-7$

A is correct.