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WHAT IS THIS

Tailsy

Tailsy

if the nineth lion ate the sun.
Pronoun
she
WHAT DOES IT WANT FROM ME

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MY TEXTBOOK IS LIKE 'DURRR WORK IT OUT YOURSELF NO EXAMPLES :D :D :D' AND MY DAD IS AWOL

I'M SURE OPAL'S MATHS TEST WILL HURT MY BRAIN MORE BUT I MEAN

WHAT?? DO THEY WANT ME TO PASS THIS EXAM OR NOT

(a I can do. It's b that make me go ?????)
 
Find the lengths of two adjacent sides (say, QR and RS) and set their products equal to 80 - 12x - 48/x. That should actually give you the exact answer, I'm not sure why you'd need to fuck around with an inequality.

QR(RS) [in terms of x] = 80 - 12x - 48/x
 
oh look, here's 4
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and this one isn't numbered 5 but oh well
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If we differentiate 80 - 12x - 48/x with respect to x, we get -12 + 48/x^2, which is zero when 48/x^2 = 12 or 12x^2 = 48. Thus x^2 = 4 and x = 2 or x = -2. As x cannot be -2, we can ignore that possibility and focus instead on x = 2. If x is less than 2, say 1, -12 + 48/x^2 is -12 + 48/1 = 36, a positive number. Thus A is rising when x is less than 2. If x is greater than 2, such as 4, -12 + 48/x^2 = -12 + 48/16 = -12 + 3 = -9, a negative number, so A is declining when x is greater than 2. Thus, the greatest value for A is obtained when x is exactly 2, and the least is obtained when x is at either of the boundaries. First, if x = 1, A = 80 - 12 - 48 = 20. If x = 4, A = 80 - 12*4 - 48/4 = 80 - 48 - 12 = 20 as well, making both of them give the least possible A. When x = 2, A = 80 - 12*2 - 48/2 = 80 - 24 - 24 = 32, the highest possible A.

There could be a simpler solution, but I'm tired and this should at least be correct.
 
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