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A circle has a diameter with end points at 3+18i and 7-6i. Which point is also on the circle ?

2 Answers

5 votes

Answer:

D. 14+11i

Explanation:

That is if they meant -3+18i

User Joe Majewski
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4.8k points
3 votes

Answer:

One point that is also on the circle is 7 + 18i.

Explanation:

Data:

End points of diameter at 3+ 18i and 7 – 6i.

Calculations

Centre of circle:

The centre is at the middle of the end points.

(x, y) = ((x₁ + x₂)/2, (y₁ + y₂)/2)

= ((3+7)/2, (18i – 6 i)/2))

= (10/2, 12i/2)

= (5, 6i)

Radius:

The centre is at (5, 6i). A point on the circumference is (3, 18i)

The distance between the two points is given by

r² = (x₂ - x₁)² + (y₂ - y₁)²

= (3 - 5)² + (18 - 6)²

= (-2)² + (12)²

= 4 + 144

= 148

r = √148

Equation for circle

The general equation for a circle is

(x – h)² + (y - k)² = r² Substitute values for h, k

( x - 5)² + (y - 6)² = 148

Points on circle:

Any point that satisfies the above equation is a point on the circle.

There are many solutions, but one point that works is 7 + 18i (see graph below).

For example,

(7 - 5)² + (18 - 6)² = 2² + 12² = 4 + 144 = 148

A circle has a diameter with end points at 3+18i and 7-6i. Which point is also on-example-1
User Jinu P C
by
5.4k points