Question

Find the value of y for which the points A(-3, 9), B(2,y) and C(4,-5) are collinear.

Answer 1

Answer:  For what value of P, are the points (- 3, 9), (2,p) and (4, - 5) collinear? ... x₁ = -3 x₂ = 2 x₃ = 4 y₁ = 9 y₂ = p y₃ = -5. For the points to be collinear :- ... If a+b+c=9 and ab+ bc + ca= 40, then find the value of a^2+b^2+c^2.

Step-by-step explanation:

Answer 2

Answer:

x₁ = -3   

x₂ = 2

x₃ = 4

y₁ = 9

y₂ = p

y₃ = -5

For the points to be collinear :-

x₁(y₂  -y₃) + x₂(y₃ - y₂) + x₃(y₁ - y₂) = 0

-3( p - (-5)) + 2(-5 - 9) + 4( 9 - p) = 0

-3( p + 5) + 2(-14) + 4( 9 - p) = 0

-3p - 15 - 28 + 36 - 4p = 0

-7p - 7 = 0

-7p = 7

p = 7/-7

p = -1