Data Sufficiency (DS) | Re: If x is a positive integer, is the value of y - z at least twice the

Given: x is a positiveinteger

Asked: Is the value of y - z at least twice the value of\(3^x - 5^x\) ?
\(y-z \geq 3^x - 5^x\)
(1)\(y = 3^{x + 1}\) and\(z = 5^{x + 1}\)
\(y = 3^{x + 1} = 3*3^x\)\(z = 5^{x + 1}=5*5^x\)
\(y-z = 3*3^x - 5*5^x = 2(3^x - 5^x) + (3^x - 3*5^x)\)\(5^x > 3^x\) when x is a positive integer
\((3^x - 3*5^x) < 0\)\( y-z = 3*3^x - 5*5^x =\)
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