Question

Let x2 + y2 = 10 x be equation of a circle and let P (7,-11) be a point. Then P is a)on the circle b)inside the circle c)outside the circle d)None of these​

Answer 1

Answer: (c) Outside the circle

Explanation:

Let us replace x with 7 in the equation

x² + y² = 10x
⇒ 7² + y² = 10×7
⇒ y² = 70 - 49
⇒ y = √21 = ±4.58 = 4.58, -4.58

So for the point to be in the circle, the y coordinate of the point needs to be between √21 and -√21

We observe -11 isn't between the specified numbers, nor is it one of them. Hence point P (7, -11) is outside the circle

Hope my answer helped