Expression of a variable from formula - examples - page 18
- Boys and girls
There are 28 girls in the hall. 5/7 of all children are boys. How many children and how many boys are there?
The area of trapezium is 35 cm2. Find its altitude if the bases are 6cm and 8 cm.
- Circle chord
Calculate the length of the chord of the circle with radius r = 10 cm, length of which is equal to the distance from the center of the circle.
- The rope
A 68 centimetre long rope is used to make a rhombus on the ground. The distance between a pair of opposite side corners is 16 centimetres what is the distance between the other two corners?
- Third member
Determine the third member of the AP if a4=93, d=7.5.
Alley measured a meters. At the beginning and end are planted poplar. How many we must plant poplars to get the distance between the poplars 15 meters?
- Solve equation
solve equation: ?
- Hexagon cut pyramid
Calculate the volume of a regular 6-sided cut pyramid if the bottom edge is 30 cm, the top edge us 12 cm, and the side edge length is 41 cm.
- Right triangle from axes
A line segment has its ends on the coordinate axes and forms with them a triangle of area equal to 36 sq. Units . The segment passes through the point ( 5,2). What is the slope of the line segment. ?
- Free fall
How long does the stone fall freely into a depth of 80m? What speed will it hit the bottom of the abyss?
he rectangular ABCD trapeze, whose AD arm is perpendicular to the AB and CD bases, has area 15cm square. Bases have lengths AB = 6cm, CD = 4cm. Calculate the length of the AC diagonal.
- Unknown number 17
Milada said, I am thinking of a number such that I evaluate expression x1/3, the value of the expression would be 5. Which number Milada thinking?
- Area of iso-trap
Find the area of an isosceles trapezoid, if the lengths of its bases are 16 cm, and 30 cm, and the diagonals are perpendicular to each other.
- Circle - AG
Find the coordinates of circle and its diameter if its equation is: ?
- Three painters
The three painters have painted bridge. The first would work done in 5 days, the second in 6 days, and the third in 7.5 days. How long will the bridge work if they work together?
- Trapezoid - intersection of diagonals
In the ABCD trapezoid is AB = 8 cm long, trapezium height 6 cm, and distance of diagonals intersection from AB is 4 cm. Calculate trapezoid area.
- Equation of circle
find an equation of the circle with indicated properties: a. center at (-3,5), diameter 20. b. center at origin and diameter 16.
- Surface of cubes
Peter molded a cuboid 2 cm, 4cm, 9cm of plasticine. Then the plasticine split into two parts in a ratio 1:8. From each part made a cube. In what ratio are the surfaces of these cubes?
- Equation of circle 2
Find the equation of a circle which touches the axis of y at a distance 4 from the origin and cuts off an intercept of length 6 on the axis x.
Simplify the following problem and express as a decimal: 5.68-[5-(2.69+5.65-3.89) /0.5]