Triangle - 7th grade (12y) - math problems

Number of problems found: 192

  • Gardens
    garden The area of the square garden is 3/4 of the area of the triangular garden with sides of 80 m, 50 m, 50 m. How many meters of the fence do we need to fence a square garden?
  • A cliff
    cliff A line from the top of a cliff to the ground passes just over the top of a pole 5 ft high and meets the ground at a point 8 ft from the base of the pole. If the point is 93 ft from the base of the​ cliff, how high is the​ cliff?
  • Poplar shadow
    shadow_1 The nine-meter poplar casts a shadow 16.2 m long. How long does a shadow cast by Peter at the same time, if it is 1.4 m high?
  • Height
    triangle_rt1 The content of the triangle is 35 cm2. The length of the base is 10 cm. Determine the length of the height on the base.
  • Chimney and tree
    shadow Calculate the height of the factory chimney, which casts a shadow 6.5 m long in the afternoon. At the same time, a 6 m high tree standing near it casts a shadow 25 dm long.
  • Similar triangles
    triangles_2 Triangle A'B'C 'is similar to triangle ABC, whose sides are 5 cm, 8 cm, and 7 cm long. What is the length of the sides of the triangle A'B'C ' if its circumference is 80 cm?
  • The triangles
    triangle_rt_taznice The triangles ABC and A'B'C 'are similar with a similarity coefficient of 2. The angles of the triangle ABC are alpha = 35°, beta = 48°. Determine the magnitudes of all angles of triangle A'B'C '.
  • Similar triangles
    triangles_1 In the triangle DEF is DE = 21cm, EF = 14.7cm, DF = 28cm. The triangle D´E´F´ is similar to the triangle DEF. Calculate the lengths of the sides of the triangle D´E´F´ if the similarity coefficient is one-seventh.
  • Surface of pyramid
    jehlan_1 In a regular quadrilateral pyramid, the height of the sidewall is equal to the length of the edge of the base. The content of the sidewall is 32 cm2. What is the surface of the pyramid?
  • Interior angles
    triangles_1 Calculate the interior angles of a triangle that are in the ratio 2: 3: 4.
  • The angles ratio
    123_triangle The angles in the ABC triangle are in the ratio 1: 2: 3. find the sizes of the angles and determine what kind of a triangle it is.
  • The triangles
    triangle1 The triangles KLM and ABC are given, which are similar to each other. Calculate the lengths of the remaining sides of the triangle KLM, if the lengths of the sides are a = 7 b = 5.6 c = 4.9 k = 5
  • Lookout tower
    marhat Calculate the height of a lookout tower forming a shadow of 36 m if at the same time a column 2.5 m high has a shadow of 1.5 m.
  • Height to the base
    triangle The triangle area is 35 cm ^ 2. The size of the base is 10 cm. Find the length of height to the base.
  • Altitude difference
    promile What a climb in per mille of the hill long 4 km and the altitude difference is 6 meters?
  • Triangular prism
    prism_rt Calculate a triangular prism if it has a rectangular triangle base with a = 4cm and hypotenuse c = 50mm and height of the prism is 0.12 dm.
  • Horizontal distance
    road_2 The road has a gradient of 8%. How many meters will the road rise on a horizontal distance of 400m?
  • Isosceles triangle
    iso_tr_1 In an isosceles triangle, the length of the arm and the length of the base are in ration 3 to 5. What is the length of the arm?
  • MO Z8–I–6 2018
    lich_1 In the KLMN trapeze, KL has a 40 cm base and an MN of 16 cm. Point P lies on the KL line so that the NP segment divides the trapezoid into two parts with the same area. Find the length of the KP line.
  • Perpendicular prism
    hranol3b_2 Calculate the volume of the perpendicular prism if its height is 60.8 cm and the base is a rectangular triangle with 40.4 cm and 43 cm legs.

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See also our trigonometric triangle calculator. See also more information on Wikipedia.