(1 point) The perimeter of a rectangle is 220 feet. Describe the possible length
ID: 3114384 • Letter: #
Question
(1 point) The perimeter of a rectangle is 220 feet. Describe the possible lengths of a side if the area of the rectangle is not to exceed 2400 square feet. Your answer should be one interval in each box. Get help entering answer See a similar example (.PDF) or in the interval Note: Use INF or -INF for oo or-o, respectively. Make sure your answer is in interval notation, e.g., an answer of 2 r 6 should be entered as 2, 6, etc. Enter "()" without quotes there is no solution (the empty set). use the letter U for union. e.g., an answer of rExplanation / Answer
perimeter = 200 feet
area should not exceed 2400 square feet
area = xy <= 2400
2 ( x+ y ) = 200
x+y = 100
y = 100 - x
( 100 - x ) x <= 2400
100x - x^2 <= 2400
on solving we get
x <= 40
x >= 60
the length of a side is in the interval ( -infinity , 40 ] U [ 60 , infinity )
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.