Line AC is tangent to the circle centered at O with radius 3 units. The length of segment AC is 4.5 units. Find the length of segment AB

What are the measures of ∠a, ∠b, ∠c and ∠d? explain how to find each of the angles. measure need asap

Acircle has a diameter will endpoints of (-2,8) and (6, 4). what is the center of the circle

Money off coupons have been circulated to 300 households. only 2/5 of these were redeemed (used) in the local supermarket to get a free shampoo. what fraction of coupons were unused? (ps: write how you got the answer)