Question 962275
(For wide-screen, it's 16/9.)  Could you use to make it only one variable and find the measurements for a wide-screen TV with 40 inches as its diagonal?
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d^2 = W^2 + H^2
W/H = 16/9 --> W = 16H/9
d^2 = (16H/9)^2 + H^2 = 337H^2/81
d = sqrt(337)*H/9
H = 9d/sqrt(337)
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W = 16d/sqrt(337)
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