A line includes the points (4,1) and (8, 2). What is its equation in slope-intercept form?

Write your answer using integers, proper fractions, and improper fractions in simplest form.

Respuesta :

Answer:

[tex]y = \frac{1}{4} x[/tex]  

Step-by-step explanation:

1) First, find the slope of the equation. Use the slope formula [tex]m= \frac{y_2-y_1}{x_2-x_1}[/tex]. Substitute the x and y values of the given points into the formula and solve:

[tex]m = \frac{(2)-(1)}{(8)-(4)} \\m = \frac{2-1}{8-4}\\m = \frac{1}{4}[/tex]

Thus, the slope is [tex]\frac{1}{4}[/tex].

2) Now, use the point-slope formula [tex]y-y_1 = m (x-x_1)[/tex] to write the equation in point-slope form (from there we can convert it to slope-intercept). Substitute values for [tex]m[/tex], [tex]x_1[/tex], and [tex]y_1[/tex].

Since [tex]m[/tex] represents the slope, substitute [tex]\frac{1}{4}[/tex] for it. Since [tex]x_1[/tex] and [tex]y_1[/tex] represent the x and y values of one point the line intersects, choose any of the given points (it doesn't matter which one, the end result will be the same) and substitute its x and y values into the formula as well. (I chose (4,1), as seen below.) Then, isolate y to put the equation in slope-intercept form and find the answer.

[tex]y-(1) = \frac{1}{4} (x-4)\\y-1 = \frac{1}{4} x-1\\y = \frac{1}{4} x+0\\y=\frac{1}{4}x[/tex]