9th grade (14y) + quadratic equation - examples

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  1. Two workers
    workers_20 Two workers should fulfill certain task together for 5 days. If the first worker increased their performance twice and second twice fell, it took them just four days. For how many days would handle the entire task first worker himself?
  2. 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.
  3. Pool
    pool If water flows into the pool by two inlets, fill the whole for 9 hours. First inlet filled pool 8 hour longer than second. How long pool is filled with two inlets separately?
  4. Cuboid
    cuboid Cuboid with edge a=14 cm and body diagonal u=42 cm has volume V=10976 cm3. Calculate the length of the other edges.
  5. Right triangle Alef
    r_triangle The perimeter of a right triangle is 132 cm, the hypotenuse is 55 cm long. Determine the lengths of the legs.
  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. Right
    r_triangle_1 Determine angles of the right triangle with the hypotenuse c and legs a, b, if: ?
  8. Right triangle
    righttriangle Legs of right are in ratio a:b = 5:8. Hypotenuse has a length of 16 dm. Calculate the perimeter and area of the triangle.
  9. R triangle
    right_triangle_1 Calculate the area of a right triangle whose longer leg is 9 mm shorter than the hypotenuse and 4 mm longer than the shorter leg.
  10. Tangents
    tangents To circle with a radius of 98 dm from the point A guided two tangents. The distance of both points of contact is 155 dm. Calculate the distance from point A and circle centre.
  11. Rhombus and inscribed
    rhombus_2 Rhombus has side a = 72 cm, the radius of the inscribed circle is r = 10 cm. Calculate the length of its two diagonals.
  12. 2nd class variations
    cards From how many elements you can create 6480 variations of the second class?
  13. Euclid1
    pravitko Right triangle has hypotenuse c = 15 cm. How large sections cuts height hc=7 cm on the hypotenuse c?
  14. Trains
    trains_toys From station 130 km away started passenger train and after 2.8 hours after the express train, which travels 24 km an hour more. Express train finish journey 14 minutes early. Calculate the average speed of this two trains.
  15. RT - hypotenuse and altitude
    pravy_trojuholnik Right triangle TWS has hypotenuse s=202 km and altitude to s is 99 km. How long are hypotenuse segments?
  16. 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.
  17. Tank
    barrel_1 In the middle of a cylindrical tank with a bottom diameter 350 cm is standing rod which is 31 cm above the water surface. If we bank rod its end reach surface of the water just by the tank wall. How deep is the tank?
  18. Cinema
    cinema Cinema auditorium is built for 1740 people. The first row is planned for 29 seats and each next gradually 2 more. How many rows of seats will have auditorium?
  19. Euler problem
    euler Someone buys a 720 tolars towels. If it was for the same money of 6 more towels, it would be 6 tolars cheaper each. How many were towels?
  20. Rectangle
    obdlznik_torta Area of rectangle is 1430. Its length is 29 larger than the width. What are the dimensions of the rectangle?

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