Question

Write an equation of the line that passes through a pair of points: On a coordinate plane, a line goes through (4, 1) and (5, 2). a. y = x + 3 c. y = -x + 2 b. y = x - 3 d. y = -x - 2 Please select the best answer from the choices provided A B C D

Answer 1

b. y = x - 3

Explanation:

The general form of the equation of the line is y = mx + c.

1) Find for m (gradient) using the following formula:

m = y2 - y1 / x2 - x1

Substitute the values into it and solve for m.

m = 2 - 1 / 5 - 4

m = 1 / 1

m = 1

2) Substitute into m of the y = mx + c.

y = 1x + c

3) Choose one the coordinates that the line goes through ((4, 1) or (5, 2)) to find c (y-intercept). I will choose (4, 1). Then, substitute your chosen coordinates into your newfound equation (y = 1x + c)

1 = 1(4) + c

1 = 4 + c

1 - 4 = c

-3 = c

Substitute -3 in place of c.

y = 1x - 3, which can be simplified to y = x - 3. Therefore, the correct choice is b.