AB is tangent to circle C. Find the value of r.

3

Step-by-step explanation:

a tangent to a circle makes right angle with the radius at that point ( here the point is B)

thus,

ABC is a right angled triangle

By Pythagoras theorem :-

By Pythagoras theorem :-AC² = AB² + BC²

(r + 2)² = 4² + r²

r² + 4 + 4r = 16 + r²

subtracting r² from both sides and taking 4 common

4(1 + r) = 16

diving both sides by 4

1 + r = 4

r = 3 units

ans is 3

Step-by-step explanation:

<ABC = 90°

SO USING pythagoras theorem

h^2= p^2+ b^2

I.e,

AC^2 = BC^2+ AB^2

or, (r+2)^2= r^2 +4^2

or, r^2+4r+4 = r^2 +16

or, 4r = 16-4

or, r= 12÷4

or, r =3

-7

step-by-step explanation:

x^2 + 18x + 74 = (x + 9)^2 - 81 + 74

= (x + 9)^2 - 7.

so q = -7.