Perimeter and Area in the Coordinate Plane of Algebra

University:
High School
Course:
High School Algebra
Academic year:

2021
Views:

346

Pages:

4
Author:

fuse15gc

Perimeter and Area in the Coordinate Plane List of terms you should recognize in a picture and apply formula (as covered in class) polygon:1 Closed, straight-sided shape n-gon: a name for any polygon n = any number of sides I want convex: polygons that have points going outwards concave: polygons that have points going inwards side: Segment that makes up the polygon vertex: intersection of two sides Extra Practice In Exercises 1-4, classify the polygon by the number of sides. Tell whether it is convex or concave. 5-sides = pentagon Concave 8-sides = octagon Convex 8-sides = octagon Concave 12-sided = dodecagon Convex Extra Practice In Exercises 5-8, find the perimeter and area of the polygon with the given vertices. 5. X(2, 4), Y(0, -2), Z(2, -2) Area: 1/2 * b * h = 1/2 * (2) * (6) = 6 Perimeter: XY + YZ + XZ = √[(0 - 2)² + (-2 - 4)²] + 6 + 2 = √(4 + 36) + 8 = √40 + 8 P = √40 + 8 6. P(1, 3), Q(1, 1), R(-4, 2) Area: 1/2 * b * h = 1/2 * (5) * (2) = 5 Perimeter: PQ + QR + PR = 2 + √(1 + 25) + √(1 + 25) = 2 + 2√26 P = 2 + 2√26 7. J(-4, 1), K(-4, -2), L(6, -2), M(6, 1) Area: b * h = (10) * (3) = 30 Perimeter: JM + ML + KL + JK = 10 + 3 + 10 + 3 = 26 8. D(5, -3), E(5, -6), F(2, -6), G(2, -3) Area: b * h = (3) * (3) = 9 Perimeter: 3 + 3 + 3 + 3 = 12 Extra Practice In Exercises 9-14, use the diagram. 9. Find the perimeter of ∆ABD Perimeter = AB + BD + DA = 5 + 6 + √5² + 6² = 11 + √25 + 36 = 11 + √61 P = 11 + √61 10. Find the perimeter of ∆BCD Perimeter = BD + BC + CD = 6 + √4² + 3² + √4² + 3² = 6 + √16 + 9 + √16 + 9 = 6 + √25 + √25 = 6 + 5 + 5 P = 16 11. Find the perimeter of quadrilateral ABCD Perimeter = AD + AB + BC + CD = 6 + 5 + 5 + 5 = 21