# Angle Problems

#### Number of problems found: 584

• A kite ABCD is a kite. Angle OBC = 20° and angle OCD = 35°. O is the intersection of diagonals. Find angle ABC, angle ADC and angle BAD.
• Angle Draw angle |∠ ABC| = 130° and built its axis. What angle is between axis angle and arm of angle?
• Neighbor angle For 136° angle calculate size of adjacent angle on one side of a straight line.
• The second The second angle of a triangle is the same size as the first angle. The third angle is 12 degrees larger than the first angle. How large are the angles?
• Obtuse angle The line OH is the height of the triangle DOM, line MN is the bisector of angle DMO. obtuse angle between the lines MN and OH is four times larger than the angle DMN. What size is the angle DMO? (see attached image)
• Largest angle of the triangle What is the largest angle of the triangle if the second angle is 10° greater than twice the first and the third is 30° smaller than the second?
• Angle at the apex In an isosceles triangle, the angle at the apex is 30° greater than the angle at the base. How big are the internal angles?
• Trapezium internal angles A trapezium where AB is parallel to CD, has angle A : angle D = 4 :5, angle B = 3x-15 and angle C = 4x+20. Find angle A, B, C and D.
• Triangles Find out whether given sizes of the angles can be interior angles of a triangle: a) 23°10',84°30',72°20' b) 90°,41°33',48°37' c) 14°51',90°,75°49' d) 58°58',59°59',60°3'
• Reference angle Find the reference angle of each angle:
• ABCD AC= 40cm , angle DAB=38 , angle DCB=58 , angle DBC=90 , DB is perpendicular on AC , find BD and AD
• Scalar dot product Calculate u.v if |u| = 5, |v| = 2 and when angle between the vectors u, v is: a) 60° b) 45° c) 120°
• Refractive index The light passes through the interface between air and glass with a refractive index of 1.5. Find: (a) the angle of refraction if light strikes the interface from the air at an angle of 40°. (b) the angle of refraction when light strikes the glass interfa
• Six-sided polygon In a six-sided polygon. The first two angles are equal, the third angle is twice (the equal angles), two other angles are trice the equal angle, while the last angle is a right angle. Find the value of each angle.
• Outer angles The outer angle of the triangle ABC at the A vertex is 71°40 ' outer angle at the vertx B is 136°50'. What size has the inner triangle angle at the vertex C?
• Lift The largest angle at which the lift rises is 16°31'. Give climb angle in permille.
• Internal angles Find the internal angles of the triangle ABC if the angle at the vertex C is twice the angle at the B and the angle at the vertex B is 4 degrees smaller than the angle at the vertex A.
• Complementary angles Two angles are complementary. If one angle measures 10°, what is the measure of the second angle?
• Similarity Are two right triangles similar to each other if the first one has an acute angle 70°, and the second one has an acute angle 20°?
• Building The building I focused at an angle 30°. When I moved 5 m building I focused at an angle 45°. What is the height of the building?

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