Exercise 119 Page 139

a To find the area of the figure, we will divide it into two rectangles.

Having identified the width and height of the rectangles, we can calculate their individual areas by multiplying these dimensions and then add them to obtain the total area. Area: ( 12)( 5)+( 10)( 8)=140 inches^2

b The area of a triangle is the product of the base and height divided by 2. The height is drawn from a vertex of the triangle and perpendicular to the opposite side, the base.

With this, we can calculate the area of the triangle. Area: 1/2(3)(8)=12 cm^2

c Assuming that this is a parallelogram, the area is calculated by multiplying it's base and height. If we rotate it, these are easier to spot.

With this, we can calculate the area of the parallelogram. Area: (9)(13)=117 feet^2

d To calculate the area of the trapezoid, we can divide it into a rectangle and two triangles. Notice that we will assume that this is an isosceles trapezoid which means the triangles are congruent.

By calculating the individual areas and adding them, we get the total area of the figure. Again, note that the triangles are congruent so we can calculate their combined area by determining one of them and then multiply by 2. Area: 2(1/2( 1.5)( 6)) +( 8)( 6)=57 m^2

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Exercise 119 Page 139

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