Simple geometry formulas



1. Parallelogram (squares rectangular or rhomboidal) = the product of the length of one side X by perpendicular height.

2. Triangle = product of base X by one-half the perpendicular height.

3. Triangle--Area from 3 sides given. From the half sum of the three sides subtract each side separately; multiply the half sum and the three remainders together, and the square root of the product will be the area.

4. Trapezoid = the sum of the two parallel sides X by half the perpendicular height.

5. Circle = the square of the diameter X 0.7854, or square of the circumference X 0.07958.

6. Sector of a Circle = radius of the circle X by onehalf the arc of the sector.

7. Segment of a Circle.--Find the area of a sector of a circle having the same arc, and deduct the triangle formed between the two radii and the chord of the arc.

AREA OF SOLIDS:

8. Cube. 9. Parallelopipidon.} = { Sum of area of sides and bases. 10. Prism.

11. Cylinder = circumference of base X height + area of bases.

12. Cone. } = {Circumference of bases X one-half slant height + area of

13. Pyramid. base.

Sphere = square of diameter X 3.1416.

French square metre, 1550.85 square inches = 10.7698 square feet.





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