Expression of a variable from formula - examples

  1. Trapezoid MO-5-Z8
    lichobeznik-stredni_pricka_2 Trapezoid KLMN has bases 12 and 4 cm long. The area of triangle KMN is 9 cm2. What is the area of the trapezoid KLMN?
  2. Trapezoid 15
    trapezoid3 Area of trapezoid is 266. What value is x if bases b1 is 2x-3, b2 is 2x+1 and height h is x+4
  3. Isosceles right triangle
    IsoscelesRightTriangle Contents of an isosceles right triangle is 18 dm2. Calculate the length of its base.
  4. Isosceles triangle
    triangles_8 Calculate area and perimeter of an isosceles triangle ABC with base AB if a = 6 cm, c = 7 cm.
  5. Cylinder - h
    cylinder_2 Cylinder volume is 129 cm3. Base radius is 3 cm. Calculate the height of the cylinder.
  6. MO SK/CZ Z9–I–3
    ball_floating_water John had the ball that rolled into the pool and it swam in the water. Its highest point was 2 cm above the surface. Diameter of circle that marked the water level on the surface of the ball was 8 cm. Determine the diameter of John ball.
  7. Theater
    SND The theater has in each row with 11 seats. Ticket to the first 8 rows is for 198 KČ. In next rows is for 84 KČ. The theater was completely sold out. Revenue was 34980 KČ. How many rows are in the theater?
  8. Garden
    garden_2 Father dig up the garden in 13 hours. Son in 18 hours. How many hours take dig up the garden together?
  9. Similarity of squares
    squares2_1 The ratio of the similarity of the squares ABCD and KLMN is 2.5. Square KLMN area is greater than area of a square ABCD with side a: ?
  10. Triangles
    green_triangle Equilateral triangle with side 25 cm has the same perimeter as an isosceles triangle with arm of 32 cm. Calculate the base x of an isosceles triangle.
  11. Painters
    natieraci Five painters painting the fence for eight days. How many days over will take work if paint the fence only four decorators?
  12. Harvesters
    kombajny The first harvester reaps the grain from land for 24 hours, the second harvester for 16 hours. For how many hours will take harvest by two harvesters, but the second harvester started working four hours later than the first?
  13. Cleaners
    clean Milan would clean up the room for 2.5 hours, Eric would take 10 hours. How long they swept the room together?
  14. Perimeter from area
    stvorec_6 What is the perimeter of the square if its content is 64 cm2?
  15. 7 triangle
    coloured_triangle The triangle area is 71.4 cm2. Determine the side length j if appropriate height hj = 39.3 cm.
  16. MO-Z5-3-66 tiles
    stvorce The picture shows a square tiles with side 10 dm which is composed of four identical small rectangles and squares. Circumference of small square is five times smaller than the circumference of the entire tile. Determine the dimensions of the rectangle.
  17. Expressions
    equation Expression (3a-7).(3a+7) is identical with: ?
  18. Apples 5
    apples_7 In six crates are 45 kg of apples. In five crates were the same amounth and in one crate was 3 kg of apples more. How many kg of apples were in each crate?
  19. Circle
    circle How big is area of circle if its circumference is 58.7 cm?
  20. Perimeter and legs
    RT_triangle Determine the perimeter of a right triangle if the length of one leg is 75% length of the second leg and its content area is 24 cm2.

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