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Area, Volume, and Surface Area. 8.3. Area Formulas. Continued. Area Formulas. Helpful Hint. Area is always measured in square units. When finding the area of figures, check to make sure that all measurements are in the same units before calculations are made. Radius. r.
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Area Formulas Continued.
Helpful Hint Area is always measured in square units. When finding the area of figures, check to make sure that all measurements are in the same units before calculations are made.
Radius r Given a circle of radius, r, the circumference isC = 2πr.
8 equal sectors Dividing the circle into 4 equal sectors, half the circumference, πr, is blue and the other half is red. πr r πr πr r πr 16 equal sectors 32 equal sectors πr πr r r πr πr Area of a Circle
128 equal sectors 64 equal sectors πr πr r r πr πr 2n equal sectors πr r πr Area of a Circle Notice the rectangular shape. A = lw A = (πr)r A =πr2
Plane Figures Perimeter/ Circumference Plane Figure Drawing Area P=a+ b+c Triangle P=a+b+c+d Parallelogram A=bh P = 2l+ 2w Rectangle A=lw Square P= 4s A=s2 P=a+b+c+d Trapezoid C=πd or 2πr A=πr2 Circle
Volumemeasures the number of cubic units that fill the space of a solid. The volume of a box or can is the amount of space inside. Volume Volume can be used to describe the amount of juice in a pitcher or the amount of concrete needed to pour a foundation for a house.
A polyhedronis a solid formed by the intersection of a finite number of planes. Surface Area The surface area of a polyhedron is the sum of the areas of the faces of the polyhedron. Surface area is measured in square units.
Volume The volume of a solid is the number of cubic units in the solid. 1 inch 1 centimeter 1 centimeter 1 inch 1 centimeter 1 inch 1 cubic inch 1 cubic centimeter
Rectangular Solid height width length Volume =length∙width∙ height V = lwh SA = 2lh + 2wh + 2lw
Cube side side side Volume =side∙side∙side V = s3 SA = 6s3
Sphere radius Volume =
Circular Cylinder height radius Volume= V=πr2h SA= 2πrh + 2πr2
Cone height radius Volume =
Square-Based Pyramid height side B = area of base, p = perimeter, l = slant height