What rule would you allow to test weather (x,y) is on line l
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Answer:
Step-by-step explanation:
If a point (x, y) lies on a straight line, coordinates of the point will satisfy the equation.
Slope of a line passing through two points C(4, 5) and D(8, 10),
m = [tex]\frac{y_2-y_1}{x_2-x_1}[/tex]
m = [tex]\frac{10-5}{8-4}[/tex]
m = [tex]\frac{5}{4}[/tex]
Equation of the line passing through C(4, 5) and slope m = [tex]\frac{5}{4}[/tex]
y - y' = m(x - x')
y - 5 = [tex]\frac{5}{4}(x-4)[/tex]
y = [tex]\frac{5}{4}x-5+5[/tex]
y = [tex]\frac{5}{4}x[/tex]
If point B(4, 0) lies on the line CD,
0 = [tex]\frac{5}{4}(4)[/tex]
0 = 5
Which is not true.
Therefore, point B doesn't lie on line CD.