Question

two points on the line are (-10,1) and (5,-5).if the coordinate of another point on the line is -3,what is the x-coordinate?​

Answer 1

x-coordinate = 0

Explanation:

(-10,1) , (5,-5)

m = (y₂ - y₁)/(x₂ - x₁) = ( -5 - 1 ) / ( 5 - [-10] )

= -6 / ( 5 + 10)

= -6/15 = -2/5

y - y₁ = m (x - x₁)

y - 1 = (-2/5) ( x - [-10] )

y - 1 = (-2/5) ( x + 10 )

5 * (y -1) = -2 (x + 10)

5y - 5 = -2x -20

2x + 20 + 5y -5 = 0

2x + 5y + 15 = 0

Another point (a, -3) in on this line

2 * a + 5 * (-3) = -15

2a -15 = -15

2a = -15 +15

2a = 0

a = 0

x-coordinate = 0