Find the coordinates of the point equidistant from three given points A(5,1), B(-3.-7) and
C(7,-1).
Answers
━━━━━━━━━━━━━━━━━━━━━━━━━
The given three points are A (5, 1) , B (–3, –7 ) and C (7, –1)
Let P (x, y) be the point equidistant from these three points.
So, PA = PB = PC
⇒ x² + 25 – 10x + y² + 1 – 2y = x² + 9 + 6x + y² + 49 + 14y = x² + 49 – 14x + y² + 1 + 2y
⇒ 25 – 10x + 1 – 2y = 9 + 6x + 49 + 14y = 49 – 14x + 1 + 2y
25 – 10x + 1 – 2y = 9 + 6x + 49 + 14y
⇒ 26 = 16x + 58 + 16y
⇒ 16x + 32 + 16y = 0
⇒ x + 2 + y = 0 … (1)
25 – 10x + 1 – 2y = 49 – 14x + 1 + 2y
⇒ 26 + 4x – 4y = 50
⇒ 4x – 4y = 24
⇒ x – y = 6 … (2)
Solving (1) and (2)
x = 2, y = –4
Thus, the required point is (2, –4)
━━━━━━━━━━━━━━━━━━━━━━━━━
Step-by-step explanation:
given,
the point is equidistant from A(5,1) B(-3,-7) C(7,-1)
let D(x,y) which is equidistant from three points
AD=BD=CD
_________ __________ _________
√(x-5)²+(y-1)²=√(x+3)²+(y+7)²=√(x-7)²+(y+1)²
squaring on all sides
=>(x-5)²+(y-1)²=(x+3)²+(y+7)²=(x-7)²+(y+1)²
=>x²+25-10x+y²+1-2y=x²+9+6x+y²+49+14y=x²+49-14x+y²+1+2y
=>25-10x-2y+1=9+6x+49+14y=49-14x+1+2y
Take first and second equation
=>25-10x-2y+1=9+6x+49+14y
=>25-10x-2y+1-9-6x-49-14y=0
=>-16x-16y-32=0
=>-16(x+y+2)=0
=>x+y+2=0.......................(1)
Take first equation and third equation
=>25-10x-2y+1=49-14x+1+2y
=>25-10x-2y+1-49+14x-1-2y=0
=>4x-4y-24=0
=>4(x-y-6)=0
=>x-y-6=0......................(2)
Add (1) and (2)
=>x+y+2+x-y-6=0
=>2x-4=0
=>x=4/2=2
Substitute x=2 in (1)
=>2+y+2=0
=>y=-4
(x,y)=(2,-4)
HOPE U CAN UNDERSTAND