Examples of area of plane shapes

  1. Isosceles trapezoid
    licho_1 Calculate the area of an isosceles trapezoid whose bases are in the ratio of 4:3; leg b = 13 cm and height = 12 cm.
  2. Interesting property
    rectangles Plot a rectangular shape has the interesting property that circumference in meters and the area in square meters are the same numbers. What are the dimensions of the rectangle?
  3. Square room
    kachlicky_1 What is the size of the smallest square room, which can pave with tiles with dimensions 55 cm and 45 cm? How many such tiles is needed?
  4. Rhombus
    pqrs PQRS is a rhombus. Given that PQ=3 cm & height of rhombus is given 2 cm. Calculate its area.
  5. Trapezoid - diagonal
    licho Trapezoid has a length of diagonal AC corssed with diagonal BD in the ratio 2:1. The triangle created by points A, cross point of diagonals S and point D has area 164 cm2. What is the area of the trapezoid?
  6. Spherical cap
    koule2 What is the surface area of a spherical cap, the base diameter 20 m, height 2 m.
  7. ISO triangle
    rr Calculate the area of an isosceles triangle KLM if the length of its sides are in the ratio k:l:m = 4:4:3 and has perimeter 377 mm.
  8. Logs
    tramy The log has diameter 30 cm. What's largest beam with a rectangular cross-section can carve from it?
  9. Parcel
    land_parcel Both dimensions of the rectangular parcel were increased by 26%. By how many % has increased its acreage?
  10. Parallelogram ABCD
    paralleogram_1 The area of parallelogram ABCD is 440 cm2. Points M and N are the midpoints of the sides AB and BC. What is the area of a quadrilateral MBND?
  11. Circles
    SquareCircleSquare Area of circle inscribed in a square is 14. What is the area of a circle circumscribed around a square?
  12. Do you solve this?
    rectangles_4 Determine area S of rectangle and length of its sides if its perimeter is 102 cm.
  13. Cathethus and the inscribed circle
    RightTriangleInradius In a right triangle is given one cathethus long 14 cm and the radius of the inscribed circle of 5 cm. Calculate the area of this right triangle.
  14. Rectangle
    rectangles_3 The rectangle area is 182 dm2, its base is 14 dm. How long is the other side? Calculate its perimeter.
  15. Goat and circles
    equation_nonlinear What is the radius of a circle centered on the other circle and the intersection of the two circles is equal to half the area of the first circle? This task is the mathematical expression of the role of agriculture. The farmer has circular land on which
  16. ISO Triangle V2
    triangle_3 Perimeter of RR triangle (isosceles) is 474 m and the base is 48 m longer than the arms. Calculate the area of this triangle.
  17. ISO trapezoid v2
    lichobeznik bases of Isosceles trapezoid measured 12 cm and 5 cm and its perimeter is 21 cm. What is the are of a trapezoid?
  18. Triangular prism
    hranol_3sides The base perpendicular triangular prism is a right triangle whose hypotenuse measures 5 cm and one cathetus 2 cm. Height of the prism is equal to 7/9 of the perimeter of the base. Calculate the surface area of prism.
  19. The body
    body_cubes The body on the figure consists of cubes with an edge length 10 cm. What surface has this body?
  20. Plan of the village
    mapa_1 Plan of the municipality in 1:1000 scale has plotted garden with dimensions 25 mm and 28 mm. Determine the area of gardens in ares in reality.

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