3x - 10 + x = 90
4x = 100
x = 25 degrees
F(x)=8/x, g(x)=8/x
f(g(x)) = f(8/x)=8/<span>8/x=x,
</span>g(f(x)) =g(8/x) =8/<span>8/x=x,
so </span>f(g(x)) = g(f(x)) = x. if <span>f of x equals eight divided by x and g of x equals eight divided by x
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You have to complete the square of (x²+18x+?) as well as for (y²-36y+?)
You will find: (x+9)² + (y-18)² = 36
& this is the standard equation requested
A is the answer :) I hope I made ur day :) ur welcome .. :)