Challenge: 1.6 Find the values of x and y in the diagram. Hint: System of linear equations (8y – 2x) + (9y – 2x) + (6x + y) = 180 8y – 2x = 2x – y 18y + 2x = 180 (Combine Like Terms) 9y – 4x = 0 (All terms to one side) 36y + 4x = 360 (Multiply by 2) 9y – 4x = 0 45y = 360 y = 8 9(8) – 4x = 0 72 – 4x = 0 72 = 4x 18 = x

Sect. 1.7 Introduction to Perimeter, Circumference and Area Goal 1 Reviewing Perimeter, Circumference and Area. Goal 2 Using a Problem Solving Plan

Reviewing Perimeter, Circumference and Area AREA is the calculation of the number of square units in the interior of a two- dimensional object. (Area is always measured in square units.) Perimeter is the distance around a figure

Reviewing Perimeter, Circumference and Area The distance around a Circle is called its circumference. The distance across a circle through its center is called its diameter. C =  · d or C = 2 ·  · r The Area of a circle is the number of square units inside that circle. A =  · r 2

Reviewing Perimeter, Circumference and Area A =bh Perimeter = Sum of all three sides.

Reviewing Perimeter, Circumference and Area Area of a Square A = s 2 Perimeter of a Square P = 4s

Reviewing Perimeter, Circumference and Area Area of a Rectangle A = length x width A = lw Perimeter of a Rectangle P = 2l + 2w

Reviewing Perimeter, Circumference and Area Find the perimeter and the area of a rectangle with length of 4.5 m and width of 0.5 m. Solution: Perimeter = 10 m. Area = 2.25 m 2

A road sign consists of a pole with a circular sign on the top. The top of the circle is 10 feet high and the bottom of the circle is 8 feet high. Find the diameter, radius, circumference, and area of the circle. Solution: Diameter = 2 ft. Radius = 1 ft. Circumference  6.3 ft. Area  3.1 ft 2 Reviewing Perimeter, Circumference and Area

Find the area and the perimeter of a triangle defined by the points H(- 2, 2), J(3, - 1), and K(- 2, - 4). Solution: Area is 15 square units Perimeter is approximately units. SketchpadSketchpad link

Using a Problem-Solving Plan A painter is painting one side of a wooden fence along a highway. The fence is 926 feet long and 12 feet tall. The directions say that each can will cover 2000 square feet. How many cans of paint will be needed to paint the fence? Solution: 6 cans of paint.

Using a Problem-Solving Plan You are designing a mat for a picture. The picture is 8 inches wide and 10 inches tall. The mat is to be 2 inches wide. What is the area of the mat? mat Solution: Area is 88 in 2

Homework even, even