Expression of a variable from the formula - 9th grade (14y) - math problems

Number of problems found: 554

  • Bamboo
    Bambus Bamboo high 32 feet was at a certain height broken by the wind so the bamboo top reached the ground at a distance of 16 feet from the trunk. At what height from the ground was the bamboo broken?
  • Circle's chords
    twochords In the circle there are two chord length 30 and 34 cm. The shorter one is from the center twice than longer chord. Determine the radius of the circle.
  • Trapezoid - central median
    lichobeznik-stredni_pricka The central median divides the trapezoid into two smaller trapezoids. Determines the ratio of their contents.
  • Coefficient
    gp Determine the coefficient of this sequence: 7.2; 2.4; 0.8
  • The volume
    sphere_in_cube_1 The volume of the sphere is 1 m3, what is its surface?
  • Unknown number
    5nums_1 Determine the unknown number, which double of its fourth square is equal the fifth its square.
  • Tetrahedron
    tetrahedron (1) Calculate height and volume of a regular tetrahedron whose edge has a length 4 cm.
  • Chord
    chord In a circle with radius r=60 cm is chord 4× longer than its distance from the center. What is the length of the chord?
  • TV tower
    Žižkov_tv_tower Calculate the height of the television tower if an observer standing 430 m from the base of the tower sees the peak at an altitude angle of 23°?
  • Two cyclists
    compass_1 Two cyclists started from crossing in the same time. One goes to the north speed 20 km/h, the second eastward at speed 26 km/h. What will be the direct distance cycling 30 minutes from the start?
  • Sphere cut
    odsek_gule A sphere segment is cut off from a sphere k with radius r = 1. The volume of the sphere inscribed in this segment is equal to 1/6 of the volume of the segment. What is the distance of the cutting plane from the center of the sphere?
  • Equilateral triangle
    equilateral_triangle2_1 Calculate the area of an equilateral triangle with circumference 72cm.
  • Equilateral triangle
    rs_triangle_1 The equilateral triangle has a 23 cm long side. Calculate its content area.
  • Radius
    green_circle Determine the radius of the circle, if its perimeter and area is the same number.
  • In the
    rectangle_1 In the rectangle ABCD, the distance of its center from the line AB is 3 cm greater than from the line BC. The circumference of the rectangle is 52 cm. Calculate the contents of the rectangle. Express the result in cm2.
  • Car and cyclist
    cyclist_6 Cyclist started from town at speed 18 km/h. After 1 hour 30 min started the car from town and caught up with the cyclist in 50 minutes. How fast was a car?
  • The ladder
    rebrik The ladder touch on a wall at a height of 7.5 m. The angle of the inclination of the ladder is 76°. How far is the lower end of the ladder from the wall?
  • Broken tree
    broken_tree The tree was 35 meters high. The tree broke at the height of 10 m above the ground. Top but does not fall off it refuted on the ground. How far from the base of the tree lay its peak?
  • Find the
    cuboid_1 Find the surface of the cuboid if its edges have the dimensions a, 2/3a, 2a
  • The volume 2
    cubes3_11 The volume of a cube is 27 cubic meters. Find the height of the cube.

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