(3b+1)^2=16 3b+1 = ±4 3b+1 = 4 b = 1 or 3b+1 = -4 b = 5/3
In order youngest to oldest, we have a,b,c,d where a+b+c+d = 384 c-a = 14 b = a+3 d = 20+(c+a)/2 85,88,99,112
you have a 5-12-13 triangle sin > 0 cos < 0
.79 = (1/2)^t/5730 t = 1949
Looks like you have the ratios of the increases, but I think they are asking about the final seat totals. That would be 5*1.4 : 6*1.5 : 7*1.75 = 7:9:12.25 = 28:36:49
since the numerator has degree less than the denominator, y=0 is the horizontal asymptote. Vertical asymptotes where the denominator is zero.
Since there are apparently no rational roots, and quartics are ridiculously hard to solve algebraically, I assume you are working on numerical methods. So, use any method of choice (Newton, bisection, etc.) to approximate the roots. Where do you get stuck?
x^2/9 + y^2/36 = 1
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