PROBLEM: A circle is inscribed in a quadrant of a circle whose radius is 10cm. Find the radius of the inscribed circle. Share your solution in the comment section.

Original by Erlina Ronda

]]>When two secants intersect on the circle, it forms an inscribed angle. There are three cases in which the secants may be positioned as shown in the figure below. These positions form different cases for the central angle-inscribed angle relationship. So when you prove the theorem that the measure of the inscribed angle is half […]

Original by Erlina Ronda

]]>Challenge yourself with this triangle problem. Squares were constructed on each side of triangle ABC. The free points of the squares were connected forming three more triangles. It is claimed that all the four triangles have equal area. Do they? Show that they do or don’t. Hints: Make a simpler problem. Use an isosceles triangle […]

Original by Erlina Ronda

]]>Problem In the figure, H is the midpoint of side BC of ΔABC. The points I and J are the intersection of the diagonals of square ABDE and square ACGF respectively, that is they are the centers of the square. Prove that IH and HJ are congruent and that angle IHJ is a right angle. […]

Original by Erlina Ronda

]]>Problem Two lines intersect the graph . The secant line intersects the graph at point A and B and the tangent line which is parallel to the secant, touches the graph at point E. You can read the coordinates of A and B from the graph but not E. What are the coordinates of E? […]

Original by Erlina Ronda

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