Given a circle (O) and its diameter AB. C is a point on the circle which is different from A and B. H is the projection of C on AB. I is the midpoint of CH. The line passes through I and perpendiculars with OC cut (O) at 2 points D and E. Prove that \(\Delta CDH\)is an isosceles triangle.
Let I be the incentre of acute triangle ABC with \(AB\ne AC\). The incircle \(\omega\)of ABC is tangent to sides BC, CA and AB at D, E, F respectively. The line through D pependicular to EF meets \(\omega\)again at R. Line AR meets \(\omega\)again at P. The circumcircles of triangles PCE and PBF meet again at Q. Prove that lines DI and PQ meet on the line through A perpendicular to AI.
Let I be the incentre of acute triangle ABC with \(AB\ne AC\). The incircle \(\omega\)of ABC is tangent to sides BC, CA and AB at D, E, F respectively. The line through D pependicular to EF meets \(\omega\)again at R. Line AR meets \(\omega\)again at P. The circumcircles of triangles PCE and PBF meet again at Q. Prove that lines DI and PQ meet on the line through A perpendicular to AI.
Given an acute triangle ABC, its median AM and its heights BH and CK. The line passes through A and perpendiculars with AM cuts BH and CK at D and E, respectively. Prove that \(\Delta DEM\)is an isosceles triangle.
Given a triangle ABC. D is a point on AB and E is a point on AC so that DE//BC and \(\frac{BC}{DE}=\sqrt{2}\), F is a point on BC and G is a point on AB so that FG//AC and \(\frac{AC}{FG}=\sqrt{2}\), H is a point on BC and I is a point on AC so that HI//AB and \(\frac{AB}{HI}=\sqrt{2}\). FG meets HI at X, DE meets HI at Y and DE meets FG at Z.
i) Prove that \(DY=ZE\)
ii) Find the exactly value of the ratio \(\frac{YZ}{BC}\)
Given a isoseles trapizoid ABCD ( AB paralle CD) AC is perpendicular to BD and the length of the height of the ABCD is 7cm . What is the area of the isoseles trapizoid ABCD ?
I hope to everyone help me to solution this math ! thanks
1. on the mp had 11 straight line double-1 ko in parallel C/m: 2 straight line created with each 1 degree17 < corner
2. For (O) the diameter AB. C in addition to line segment AB (C lies on the straight line AB). 2 guystangential CE and CF AB cut EF at I, the cat onlineCMN. C/m: AIM angle = angle of BIN
3. For triangle ABC outreach circle (O). Know D, E, F isthe next point, D in AC, AB, F E in B.C. Know OE = r,AB = c, AC = b, BC = a
C/m: a) 1 (a + b + c) * r = 2S (S is the area of triangle ABC)
b) if (a + b + c) (a + b-c) = 4S, the triangle ABC square
Dịch bài toán sau và giải :
"Give a right triangle ABC (Â=90) with B =40 and the line d is a the midperpendicular of the segment BC . Suppose that d AB = {E} , E of the segment BC . If BE=16 cm then the area of ABC is ... cm^2.
(round to three demical places in each step)
A . 256
B . 147,95
C . 128
D . 295,9
The area of triangle ABC is 300 . In triangle ABC, Q is the midpoint of BC, P is a point on AC between C and A such that CP = 3PA . R is a point on side AB such that the area of \(\Delta\)PQR is twice the area of \(\Delta\)RBQ . Find the area of \(\Delta\)PQR