The perimeter of a rectangle is 108cm. The ration of its length to its width is 7:2 what is the area of the rectangle in cm2?
1 answer:
Answer:
504 cm²
Step-by-step explanation:
Let the length and the width of the rectangle be L cm and W cm respectively.
Perimeter= 2(L +W)
2(L +W)= 108
L +W= 108 ÷2
L +W= 54
L= 54 -W -----(1)
<em>Cross multiply:</em>
2L= 7W -----(2)
Substitute (1) into (2):
2(54 -W)= 7W
<em>Expand:</em>
108 -2W= 7W
<em>+2W on both sides:</em>
9W= 108
<em>Divide both sides by 9:</em>
W= 108 ÷9
W= 12
<em>Substitute W= 12 into (1):</em>
L= 54 -12
L= 42
Area of rectangle
= length ×width
= LW
= 42(12)
= 504 cm²
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Answer:
The cost of basic cable television in the United States in the year 2020 will be $67.19.
Step-by-step explanation:
The linear function has the following format.
In which y(x) is the cost x years after 2000, y(0) is the initial cost, that is, the cost in 2000, and a is the slope(how much the cost changes in a year).
In 2000, the average monthly price for basic cable television in the United States was $29.99.
This means that
In 2016, the average monthly price for the same basic cable television was $59.75.
2016 is 16 years after 2000. So
Write a linear function that models the cost of basic cable television in the United States for x years after 2000.
Applying y(16).
So
Use the linear function to determine the cost of basic cable television in the United States in the year 2020.
2020 is 20 years after 2000, so this is y(20).
The cost of basic cable television in the United States in the year 2020 will be $67.19.