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2 years ago

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the area of a concrete rectangular pathway is 350m square and its perimeter pathway is 90 m.what is the length of the pathway?

1 answer:

statuscvo [17]2 years ago

5 0

X, y - the lengths of the sides of the pathway

The area of a rectangle is the product of the lengths of its sides. The area is 350 m².
$xy=350$

The perimeter of a rectangle is two times the sum of the lengths of its sides. The perimeter is 90 m.
$2(x+y)=90 \ \ \ \ \ \ |\div 2 \\
x+y=45 \ \ \ \ \ \ \ \ \ \ |-x \\
y=45-x$

Substitute 45-x for y in the first equation:
$x(45-x)=350 \\
45x-x^2=350 \\
-x^2+45x-350=0 \\
-x^2+10x+35x-350=0 \\
-x(x-10)+35(x-10)=0 \\
(-x+35)(x-10)=0 \\
-x+35=0 \ \lor \ x-10=0 \\
x=35 \ \lor \ x=10$

$y=45-x \\
\hbox{for } x=35: \\
y=45-35=10 \\ \\
\hbox{for } x=10: \\
y=45-10=35$

The dimensions of the pathway are 10 m by 35 m.
The length of the pathway is 35 m.

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2 years ago

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2 years ago

Sue played four games of golf for these games her modal score was 98 and her mean score was 100 her range of score was 10 what w

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As we know that ,

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Let highest observation be x

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2 years ago

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Answer:

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Step-by-step explanation:

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2 years ago