Plot the vertices (-2, -8), (-2, 2), and (8, 2).
What is the last vertex of the rectangle?
What is the area of the rectangle?
square units

Step-by-step explanation:

The diagonals of a rectangle have the same midpoint, so for points A, B, C, D, we must have ...

  (A+C)/2 = (B+D)/2

  D = A + C - B

  D = (-2, -8) +(8, 2) -(-2, 2) = (-2+8+2, -8+2-2)

  D = (8, -8)

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The side lengths are 2-(-8) = 10, and 8-(-2) = 10. The area is the product of the side lengths, so is 10×10 = 100 square units.

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Comment on side lengths

When the end points of one side are on the same vertical line, the length of that side is the difference of y-coordinates. When the points lie on the same horizontal line, the side length is the difference of x-coordinates.

7. 153.86 ft

8. 12.56 ft

9. 78.5 m

10. 379.94 in

11. 132.665 m

12. 12.56 yd

13. 226.865 ft

14. 113.04 ft

15. 63.585 ft

16. 254.34 m

17. 50.24 cm

step-by-step explanation:

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24

step-by-step explanation:

the graph shows 30% of students walk. 80 students were questioned, so the number that said they walk is

30% × 80 = 0.30 × 80 = 24