<h3>
Answer: shaded region has area 107 square feet</h3>
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Work Shown:
A = area of larger rectangle
A = length*width = 9*15 = 135 square feet
B = area of smaller rectangle
B = length*width = 7*4 = 28 square feet
C = area of shaded region
C = difference in areas of A and B
C = A - B = 135 - 28 = 107 square feet
It's a simultaneous equation:
Steps:
1.Number the equations..
a+b=77 -1
a-b=13 -2
2. Choose what variable you want to use. In this case I would use the "b". Since the signs in front of the "b's" are different, add the two equations together
a + b = 77
+ + +
a (-b) = 13
Which gives;
2a = 90
Then solve to find a:
2a=90
a= 90/2
a=45
3.Then plug the "a" value into any of the original equations to find the "b" value. I would use equation 1 since the all the variables are positive.
a + b = 77
(45) + b = 77
b=77-45
b=32
4.Solution
a=45
b=32
At least 14 economy and at least 5 deluxe...total of 45 seats. He makes a bigger profit from selling economy seats....so we need the most economy seats we can get.
45 seats - 5 deluxe = 40 economy
so the most profit would be 40 economy and 5 deluxe
40 economy = (40 x 30) = 1200 profit
5 deluxe = (5 x 25) = 125 profit
for a maximum profit of : $ 1325
Sorry if this is messy but I hope it helps you
Y will equal 36. You can figure this out because you know y is double the value of x. If x is 18,you can just multiply it by 2, which equals 36