Try this Drag the orange dots on any vertex to reshape the triangle. Notice the location of the orthocenter. Show
The altitude of a triangle (in the sense it used here) is a line which passes through a vertex of the triangle and is perpendicular to the opposite side. There are therefore three altitudes possible, one from each vertex. See Altitude definition. It turns out that all three altitudes always intersect at the same point - the so-called orthocenter of the triangle. The orthocenter is not always inside the triangle. If the triangle is obtuse, it will be outside. To make this happen the altitude lines have to be extended so they cross. Adjust the figure above and create a triangle where the orthocenter is outside the triangle. Follow each line and convince yourself that the three altitudes, when extended the right way, do in fact intersect at the orthocenter. Summary of triangle centersThere are many types of triangle centers. Below are four of the most common. In the case of an equilateral triangle, all four of the above centers occur at the same point.The Euler line - an interesting factIt turns out that the orthocenter, centroid, and circumcenter of any triangle are collinear - that is, they always lie on the same straight line called the Euler line, named after its discoverer.For more, and an interactive demonstration see Euler line definition. Constructing the Orthocenter of a triangleIt is possible to construct the orthocenter of a triangle using a compass and straightedge. See Constructing the the Orthocenter of a triangle.Other triangle topicsGeneral
Perimeter / Area
Triangle types
Triangle centers
Congruence and Similarity
Solving triangles
Triangle quizzes and exercises
(C) 2011 Copyright Math Open Reference. Home The point of intersection of all the three altitudes of a triangle is called the Question A orthocenter Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses B incenter No worries! We‘ve got your back. Try BYJU‘S free classes today! C centroid No worries! We‘ve got your back. Try BYJU‘S free classes today! Open in App Solution The correct option is A orthocenterThe point of intersection of all the three altitudes of a triangle is called the orthocenter.Suggest Corrections 0 Similar questions Q. The intersection point of altitudes of a triangle is called ______. Q. The point of concurrency of three altitudes of a triangle is called its Q. The point where all the
altitudes of a triangle meet is called - Q. The point of intersection of all the three perpendicular bisectors of a triangle is called . Q. The point of concurrence of the altitudes of a triangle is called View More Altitudes and Orthocenters By Pei-Chun Shih The three altitudes of a triangle intersect in a single point, called the orthocenter of the triangle. The orthocenter lies inside the triangle if and only if the triangle is an acute triangle. There are several interesting relationships between the three altitudes and the orthocenter. Here I am going to use GSP to explore them and provide proofs of the relationships. Construct the orthocenter H in a given acute triangle ABC. Let points D, E, and F be the feet of the perpendiculars from A, B, and C respectfully. Prove that + + = 1 and + + = 2. The first proof can be accomplished by using the area formula of a triangle which is half of the product of a base and its corresponding altitude. Let�s divide the triangle ABC into three small triangles: AHC, BHC, and AHB. So the area of triangle ABC equals the sum triangles AHC, BHC, and AHB: △AHC + △BHC + △AHB = △ABC Divide each side by △ABC, + + = 1 Express by the area formula of a triangle, + + = 1 Simplify, + + = 1 (Proposition 1) The second proof can be done by using the proposition 1 we have just proved above. Since BH = BE – HE, AH = AD – HD, and CH = CF – HF, then we can do the following substitution: + + = + + Simplify, = (1 - ) + (1 - ) + (1 - ) Rearrange, = 3 – ( + + ) Substitute + + for 1 and we can get + + = 3 – 1 = 2. We can explore the properties of the altitudes and orthocenters further by constructing the circumcircle of the triangle ABC and extending each altitude to its intersection with the circumcircle at corresponding points P, Q, and R. There is a relationship between the altitudes and AP, BQ, and CR which is + + = 4. We can prove it by applying the proposition 1 again here. Before using the proposition 1, let�s add some construction lines first. Connect AR, BP, and QC. We want to prove that HD = PD, HE = QE, and HF = RF. Consider △BHD and△AHE. △BHD and△AHE are similar triangles by the Angle-Angle Similarity Theorem since ∠BHD = ∠AHE and ∠BDH = 90 degrees = ∠AEH. Therefore, ∠HAE = ∠HBD. Since points A, E, C are collinear, points A, H, P are collinear, and points B, D, C are collinear, then ∠HAE = ∠PAC and ∠PBD = ∠PBC. ∠PAC = ∠PBC since they intercept the same arc PC. Hence, ∠PBD = ∠HBD. △BHD and△BPD are congruent triangles by the Angle-Side-Angle Congruence Theorem since ∠PBD = ∠HBD, BD = BD, and ∠BDH = 90 degree = ∠BDP. Therefore, HD = PD. Similarly, we can get that HE = QE and HF = RF by performing the same steps above for △ARH and△CQH. Thus, AP = AD + PD = AD + HD, BQ = BE + QE = BE + HE, CR = CF + RF = CF + HF. So, + + = + + = (1 + ) + (1 + ) + (1 + ) = 3 + + + = 3 + 1 by Proposition 1 = 4 Therefore, + + = 4. RETURN What is the intersection of 3 altitudes called?The correct option is A orthocenter. The point of intersection of all the three altitudes of a triangle is called the orthocenter.
What are the 3 altitudes of a right triangle?Altitudes of a Triangles Formulas. Why does a triangle have 3 altitudes?Altitude(s) of a Triangle. An altitude of a triangle is a segment from a vertex of the triangle, perpendicular to the side opposite that vertex of the triangle. Since all triangles have three vertices and three opposite sides, all triangles have three altitudes.
What is the name of the point where the altitudes of the sides intersect?The orthocenter is the point where all the three altitudes of the triangle cut or intersect each other. Here, the altitude is the line drawn from the vertex of the triangle and is perpendicular to the opposite side.
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