Answer:
y = 2x + 3
Step-by-step explanation:
The equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept )
Calculate m using the slope formula
m = (y₂ - y₁ ) / (x₂ - x₁ )
with (x₁, y₁ ) = (- 2, - 1) and (x₂, y₂ ) = (1, 5)
m = [tex]\frac{5+1}{1+2}[/tex] = [tex]\frac{6}{3}[/tex] = 2, thus
y = 2x + c ← is the partial equation
To find c substitute either of the 2 points into the partial equation
Using (1, 5), then
5 = 2 + c ⇒ c = 5 - 2 = 3
y = 2x + 3 ← equation of line
Answer: y = 2x + 3
Step-by-step explanation:
The formula for finding equation of line when two points are given is :
[tex]\frac{y-y_{1} }{x-x_{1}}[/tex] = [tex]\frac{y_{2}-y_{1}}{x_{2}-x_{1}}[/tex]
[tex]x_{1}[/tex] = -2
[tex]x_{2}[/tex] = 1
[tex]y_{1}[/tex] = -1
[tex]y_{2}[/tex] = 5
Substituting the values into the equation , we have
[tex]\frac{y-(-1)}{x-(-2)}[/tex] = [tex]\frac{5-(-1)}{1-(-2)}[/tex]
[tex]\frac{y+1}{x+2}[/tex] = [tex]\frac{5+1}{1+2}[/tex]
[tex]\frac{y+1}{x+2}[/tex] = [tex]\frac{6}{3}[/tex]
[tex]\frac{y+1}{x+2}[/tex] = [tex]\frac{2}{1}[/tex]
cross multiplying , we have
y + 1 = 2(x+2)
y + 1 = 2x + 4
in order to write it in slope - intercept form , we will make y the subject of formula , that is
y = 2x + 4 - 1
y = 2x + 3
