Write an equation of the line that passes through (-2, 5) and (1, 2).

Answer 1

#1 lets find the slope first, using m= (y₂ - y₁) ÷ (x₂ - x₁)

keep in mind the points ( x₁, y₁) is (-2 , 5) and (x₂ , y₂) is (1 , 2)

so, m = (2 - 5) ÷ (1 -(-2))

m = (-3) ÷ ( 1+2)

m = -3 ÷ 3 = -1

our slope, m = -1

#2 Lets use the slope to find the y- intercept using y = mx + b

y = (-1)x + b

y = -x + b is the equation of our line

let's use one of the given points (doesn't matter which one)

let's use (1 , 2) which is our (x , y)

2 = -1 + b

3 = b

#3 Lets re-write the equation y = mx + b using the values of the slope m and the y- intercept b

y = -x + 3 is our answer