"Published in Newark, California, USA"
A certain city block is in the form of a parallelogram. Two of its sides are each 421 ft. long; the other two sides are each 227 ft. in length. If the distance between the first pair of sides is 126 ft., find the area of the land in the block, and the length of the diagonals.
Solution:
To illustrate the problem, it is better to draw the figure as follows
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| Photo by Math Principles in Everyday Life |
Since the height of a parallelogram is given as well as the opposite sides, then we can solve for the area as follows
In order to solve for the diagonals of a parallelogram, we need to label further the figure above as follows
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| Photo by Math Principles in Everyday Life |
Use Pythagorean Theorem for ∆ADE, we have
Use Pythagorean Theorem for ∆DEB, we have
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| Photo by Math Principles in Everyday Life |
Use Pythagorean Theorem for ∆ACF, we have
