which equation in slope-intercept from represents the line that passes through (-1, 5) and (5, 8)
y= 1/2 x -11
y=-1/2 x +11/2
y= 1/2 x +11/2
y= -1/2 x -11/2

Respuesta :

Answer:

y= 1/2 x +11/2

Step-by-step explanation:

To find the slope

m = (y2-y1)/(x2-x1)

  = (8-5)/(5--1)

  = 3/(5+1)

  = 3/6

  = 1/2


Using point slope form of a line

y-y1 = m(x-x1)

y-5 = 1/2(x--1)

y-5 = 1/2(x+1)

Distribute

y-5 = 1/2x +1/2

Add 5 to each side

y = 1/2x + 1/2 + 5

Change 5 to 10/2

y = 1/2x + 1/2 + 10/2

y = 1/2x + 11/2

Slope-intercept form:

y = mx + b

"m" is the slope, "b" is the y-intercept (the y value when x = 0) or (0,y)


To find the slope, you can use the slope formula and plug in the two points:

(-1,5) = (x₁ , y₁)

(5,8) = (x₂ , y₂)


[tex]m=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}[/tex]

[tex]m=\frac{8-5}{5-(-1)}[/tex]

[tex]m=\frac{8-5}{5+1} =\frac{3}{6} =\frac{1}{2}[/tex]


y = 1/2x + b

To find "b", plug in either of the points into the equation:

(5,8)

y = 1/2x + b

8 = 1/2(5) + b

8 = 5/2 + b      Subtract 5/2 on both sides

8 - 5/2 = b         Make the denominators the same in order to subtract them

16/2 - 5/2 = b

11/2 = b


[tex]y = \frac{1}{2}x+\frac{11}{2}[/tex]    

The 3rd option is your answer