This is the 2018 MTAP Grade 10 Math Challenge questions 26 to 30. Questions 1-25 including can be found **here**. The pdf can be downloaded **here**. Solutions and answer will be posted later. More reviewers can be found on the **Past Tests** and **All Posts** pages.

**Questions**

26.) Find the radius of the circle with equation .

27.) Give the equation (in center-radius form) of the circle having as a diameter the segment with endpoints and .

28.) The center of a circle is on the *x*-axis. If the circle passes through and , find the coordinates of its center.

29.) If is an angle in a triangle and , find . Continue reading