4.9 Area Problems

• Objective: To solve some problems involving area.

o Warm – up:Find the area of each shaded region.

8

10

64

2

1

8

6

4.9 Area Problems

Solve.o A rectangle is 3 times as

long as it is wide. If the length is increased by 6 and the width is increased by 8m the area is increased by 108. Find the original dimensions.

o A rectangle is twice as long as it is wide. If its length is decreased by 4 and its width is decreased by 2, its area is decreased by 24. Find its original dimensions.

4.9 Area Problems

Solve.o A photograph 8 in. wide and

10 in. long is surrounded by a border 2 in. wide. To find the area of the border, you subtract the areas of the rectangles.

o Area of = Area of – Area ofborder outer inner

2

2

2

2

8

10

4.9 Area Problems

Solve.o Hector Herrera made a

rectangular fish pond surrounded by a brick walk 2 m wide. He had enough bricks for the area of the walk to be 76 m2. Find the dimensions of the pond if it is twice as long as it is wide.

o Area of = Area of – Area ofborder outer inner

2

2

2x

x

2x+4

x+42

2

4.9 Area Problems

• Homework:– Pg. 173

Written Exercises #1 – 7 odd