# Planimetrics - math problems

Study plane measurements, including angles, distances, and areas. In other words - measurement and calculation of shapes in the plane. Perimeter and area of plane shapes.

#### Number of problems found: 2136

• Center
Calculate the coordinates of the circle center: x2 -4x + y2 +10y +25 = 0
• Perimeter of square
The square has a circumference 17cm. What is its area?
• Angle
Draw angle |∠ ABC| = 130° and built its axis. What angle is between axis angle and arm of angle?
• Possible lengths
Find the most possible lengths for the third side of a triangle with sides 20 and 18.
• 10 pieces
How to divide the circle into 10 parts (geometrically)?
• Internal angles IST
Determine internal angles of isosceles trapezium ABCD /a, c are the bases/ and if: alpha:gamma = 1:3
• 9-gon
Sum of interiol angles of 9-gon is:
• Hexagon
Draw a regular hexagon inscribed in a circle with radius r=8 cm. What is its perimeter?
• Cube - wall
V kocke ABCDEFGH je ?. Aký je povrch kocky?
• Cylinder
Calculate the dimensions of rotating cylindrical containers with volume 2 l if the container's height is equal to the base's diameter.
• Sines
In ▵ ABC, if sin(α)=0.5 and sin(β)=0.6 calculate sin(γ)
• Circumscription
Calculate radius of the Circumscribed circle in the rectangle with sides 20 and 19. It can be rectangle inscribed by circle?
• Triangle
Calculate heights of the triangle ABC if sides of the triangle are a=82, b=44, and c=53.
• Completing square
Solve the quadratic equation: m2=4m+20 using completing the square method
• Quatrefoil
Calculate area of the quatrefoil which is inscribed in a square with side 6 cm.
• Pilot
How high is the airplane's pilot to see 0.001 of Earth's surface?
• Trapezium 2
Trapezium has an area of 24 square cms. How many different trapeziums can be formed ?
• Diameter
The diameter of a circular plot is 14 dm. Find the circumference and area.
• Semicircle
In the semicircle with center S and the diameter AB is constructed equilateral triangle SBC. What is the magnitude of the angle ∠SAC?
• Trigonometric functions
In the right triangle is: ? Find the value of s and c: ? ?

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