Question

the length of a tangent from a point a at a distance 5 cm from the centre of the circle is 4 cm find the radius of the circle

Answer 1

5^2=4^2 +r^2
25=16 +r^2
25-16=r^2
9=r^2
3=r

Answer 2

(4)²+(r)²=(5)²
16+(r)²=25
(r)²=25-16
(r)²=9
r=√9
r=3
HOPE IT HELPS YOU.