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

Number of problems found: 197

  • Is right triangle
    rt.JPG One angle of the triangle is 36° and the remaining two are in the ratio 3:5. Determine whether triangle is a rectangular triangle.
  • Triangle
    eq_triangle Can an equilateral triangle have a right angle?
  • 3-bracket 3
    triangle_3 Two angles in a triangle are 90° and 60°. Has triangle at least two equal sides?
  • It is rectangular?
    nice_3d Size of two of the angles in a triangle are: α=110°, β=40°. Is it a right triangle?
  • Triangle
    red_triangle For how many integer values of x can 16, 15 and x be the lengths of the sides of triangle?
  • Is right triangle or not
    triangle_rt1_2 If right triangle ABC, have sides a=13, b=11.5, c=22.5. Find area.
  • Isosceles triangle
    rr_triangle3 The circumference of the isosceles triangle is 32.5 dm. Base length is 153 cm. How long is the leg of this triangle?
  • Right triangle
    triangles_1 Right triangle ABC with side a = 19 and the area S = 95. Calculate the length of the remaining sides.
  • Is right?
    rtriangle Is a triangle with sides 51, 56, and 77 right triangle?
  • Inner angles
    rr_triangle3 The magnitude of the internal angle at the main vertex C of the isosceles triangle ABC is 72°. The line p, parallel to the base of this triangle, divides the triangle into a trapezoid and a smaller triangle. How big are the inner angles of the trapezoid?
  • Area of a triangle
    triangle1_2 What is the area of a triangle that has the base 4 1/4 and the height of 3 3/3?
  • Midpoints
    sierpinski_1 Triangle whose sides are midpoints of sides of triangle ABC has a perimeter 45. How long is perimeter of triangle ABC?
  • Angles in triangle
    angles_triangle.JPG Calculate the alpha angle in the triangle if beta is 61 degrees and 98 gamma degrees.
  • EQL triangle
    rs_triangle Calculate inradius and circumradius of equilateral triangle with side a=77 cm.
  • 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.
  • Triangle angles
    triangles_2 The angles α, β, γ in triangle ABC are in the ratio 6:2:6. Calculate size of angles.
  • Type of triangle
    237_triangle How do I find the triangle type if the angle ratio is 2:3:7 ?
  • Triangles
    green_triangle Equilateral triangle with side 40 cm has the same perimeter as an isosceles triangle with arm of 45 cm. Calculate the base x of an isosceles triangle.
  • Triangle radians
    triangle-base The size of two internal angles of a triangle ABC are α=6/18π and β=7/18π. Calculate the size of the third angle.
  • XY triangle
    triangle Determine the area of a triangle given by line 7x+8y-69=0 and coordinate axes x and y.

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See also our trigonometric triangle calculator. Triangle Problems. Examples for 7th grade (seventh).