Examples of area of plane shapes

  1. Triangle ABC
    triangles_3 Calculate the sides of triangle ABC with area 1404 cm2 and if a: b: c = 12:7:18
  2. Infinity
    circles-and-squares In a square with side 18 is inscribed circle, in circle is inscribed next square, again circle and so on to infinity. Calculate the sum of area of all these squares.
  3. Recursion squares
    squares_reccurent In the square ABCD is inscribed a square so that its vertices lie at the centers of the sides of the square ABCD.The procedure of inscribing square is repeated this way. Side length of square ABCD is a = 22 cm. Calculate: a) the sum of perimeters of al
  4. Garden
    garden_1 Area of a square garden is 6/4 of triangle garden with sides 56 m, 35 m, and 35 m. How many meters of fencing need to fence a square garden?
  5. Coins
    eur_coins Harvey had saved up a number of 2-euro coins. He stored coins in a single layer in a square. Left 6 coins. When he make square, which has one more row, missing 35 coins. How many euros he have?
  6. Scale
    pool_1 Swimming pool is long 110 m and 30 m wide. The plan of the city is shown as a rectangle with area 8.25 cm2. What scale is the city plan?
  7. Angles
    rhombus_1 Determine the interior angles of a rhombus with area 319.1 cm2 and perimeter 72 cm.
  8. Cylinders
    cylinders Area of the side of two cylinders is same rectangle of 33 mm × 18 mm. Which cylinder has a larger volume and by how much?
  9. Two squares
    squares2 Two squares whose sides are in the ratio 5:2 have sum of its perimeters 73 cm. Calculate the sum of area this two squares.
  10. Regular 5-gon
    5gon_2 Calculate area of the regular pentagon with side 7 cm.
  11. Rectangle vs square
    squares_3 The rectangle has dimensions of 13 × 10, square 8 × 8. Which shape has more area and how much above?
  12. Windows
    wall_w_windows Calculate the area of masonry to build wall with dimensions of 9 m × 4 m with 4 windows of size 64 cm × 64 cm.
  13. Carpet
    koberec The room has rectangle shape with dimensions 4 m × 3.8 m. How many meters of carpet a width of 3 need to buy to cover the entire room?
  14. Rhomboid
    parallelogram Calculate the circumference and area of the rhomboid with sides 20 and 14, with their angle 50°.
  15. Right Δ
    ruler A right triangle has the length of one leg 11 cm and length of the hypotenuse 61 cm. Calculate the height of the triangle.
  16. Area of RT
    right_triangle_sepia Calculate the area of a right triangle that hypotenuse has length 14, and one hypotenuse segment has length 5.
  17. Trapezoid MO
    right_trapezium The rectangular trapezoid ABCD with right angle at point B, |AC| = 12, |CD| = 8, diagonals are perpendicular to each other. Calculate the perimeter and area of ​​the trapezoid.
  18. Radius
    green_circle Determine the radius of the circle, if its perimeter and area is the same number.
  19. Described
    desc_circle Calculate perimeter of the circle described by a triangle with sides 478, 255, 352.
  20. Square
    square_1 Points A[-9,7] and B[-4,-5] are adjacent vertices of the square ABCD. Calculate the area of the square ABCD.

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