1 5 Using Formulas in Geometry Objectives Students

1 -5 Using Formulas in Geometry Objectives Students will be able to apply perimeter, area, and circumference formulas to solve problem. Holt Mc. Dougal Geometry

1 -5 Using Formulas in Geometry The perimeter P of a plane figure is the sum of the side lengths of the figure. The area A of a plane figure is the number of non-overlapping square units of a given size that exactly cover the figure. Holt Mc. Dougal Geometry

1 -5 Using Formulas in Geometry Remember! Perimeter is expressed in linear units, such as inches (in. ) or meters (m). Area is expressed in square units, such as square centimeters (cm 2). Holt Mc. Dougal Geometry

1 -5 Using Formulas in Geometry Holt Mc. Dougal Geometry

1 -5 Using Formulas in Geometry The base b can be any side of a triangle. The height h is a segment forms a right angle with the base. The height may be a side of the triangle or in the interior or the exterior of the triangle. Holt Mc. Dougal Geometry

1 -5 Using Formulas in Geometry What’s my base and what’s my height? Holt Mc. Dougal Geometry

1 -5 Using Formulas in Geometry Perimeter and Area with Algebra Find the area and perimeter of each figure. 1. x 2 + 4 x; 4 x + 8 2. 10 x; 4 x + 16 Holt Mc. Dougal Geometry

1 -5 Using Formulas in Geometry The circumference of a circle is the distance around the circle. “perimeter of the circle” Holt Mc. Dougal Geometry

1 -5 Using Formulas in Geometry (Pi) is often approximated as 3. 14 or Holt Mc. Dougal Geometry .

1 -5 Using Formulas in Geometry Find circumference and area of circles Find the area and perimeter of each circle. 1. 2. Holt Mc. Dougal Geometry

1 -5 Using Formulas in Geometry Find Circumference and Areas of Circles Holt Mc. Dougal Geometry

1 -5 Using Formulas in Geometry 1. 5 HW answer 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 12 ft 6 ft 2 2. 4 ft or ft P 9. 6 m; A 5. 76 m 2 P 2 x 20; A 7 x 21 circumference C 44 mi; A 154 mi 2 2 in. 19 m 12. 5 mm Holt Mc. Dougal Geometry

1 -5 Using Formulas in Geometry Apply Formulas of Perimeter, Circumference and Areas Holt Mc. Dougal Geometry

1 -5 Using Formulas in Geometry Holt Mc. Dougal Geometry

1 -5 Using Formulas in Geometry Group wprk- Application in Real LIfe A landscaper is installing a brick patio in the backyard. He is building a rock wall around the perimeter of the patio. 1. What is the area needed for the brick patio? 2. What is the perimeter needed for building the brick wall? 28. 56 ft. Holt Mc. Dougal Geometry