Question

Instructions: Determine if AB is tangent to the circle.

AB
20
B
12
수 to the circle.
16

Answer 1

Explanation:

to be a tangent, it would have to have a 90° angle with the radius (12).

and that would make the triangle ABCenter of the circle a right-angled triangle.

and then Pythagoras must apply :

c² = a² + b²

with c being the Hypotenuse (the baseline opposite of the 90° angle). in our case the 20-line.

so,

20² = 12² + 16²

400 = 144 + 256 = 400

yes, it is confirmed, because the Pythagoras principle applies, it is a right-angled triangle, and therefore AB is indeed a tangent.

Answer 2

the line AB is tangent to the circle

Explanation:

we have :

16² + 12² = 256 +144 = 400

On the other hand:

20² = 400

Then

16² + 12² = 20²

Then

According to the Pythagorean theorem:

The line AB is perpendicular to the radius of the circle

Which means the line AB is tangent to the circle.