C2 Coordinate geometry
Maths and statistics discussion, revision, exam and homework help.
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C2 Coordinate geometryHere are the questions:
1) The points A(-3,19), B(9,11) and C(-15,1) lie on the circumference of a circle. Find the coordinates of the centre of the circle.
Midpoint = (-3+9/2, 19+11/2) = (-3,15)
11-19/9+3 = -3/4
4y=-3x+51
Did the same for the other one, and got: M.P.(9,10) and 2y=3x-7
(4y=-3x+51) + (2y=3x+7) -> 6y=44 -> y=44/6=22/3
Is this right so far?
2) Find the distance between (-4a,0) and (3a,-2a)
d=√[(3a+4a)2+(-2a-0)2]
=√[(7a)2+(-2a)2]
=√[49a2+4a2 = √53a2
Would the answer be √53a or 53a? -
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Re: C2 Coordinate geometryNo it isn't(Original post by Math12345)
It is 53a, because the square root cancels out with the squared. Remember it is sqrt(53a)^2
