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If f(x, y) = x2y and f(a, b) = 6, what is f(2a, 4b)? [#permalink]
30 Jul 2018, 10:13
Question Stats:
71% (00:39) correct
28% (01:40) wrong based on 7 sessions
If \(f(x, y) = x^2y\)and \(f(a, b) = 6\), what is \(f(2a, 4b)\)?
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Re: If f(x, y) = x2y and f(a, b) = 6, what is f(2a, 4b)? [#permalink]
05 Aug 2018, 17:09
someone please explain?



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Re: If f(x, y) = x2y and f(a, b) = 6, what is f(2a, 4b)? [#permalink]
06 Aug 2018, 20:44
kruttikaaggarwal wrote: someone please explain? Sure thing. The equations we are given is that \(f(x,y) = x^2 y\) and \(f(a,b) = 6\) in order to find out \(f(2a,4b)\). Using the first equation, we can change \(f(2a,4b)\) into another form. \((2a)^2 * 4b\) \((2a)^2 * 4b\) \(4 * a^2 * 4 * b\) \(16 * a^2 b\) (does this \(a^2 b\) look familiar? it's the second equation we were given, so we can substitute this value for 6) \(16 * 6 = 96\) There's your answer



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Re: If f(x, y) = x2y and f(a, b) = 6, what is f(2a, 4b)? [#permalink]
12 Aug 2018, 07:00
ExplanationThe problem provides the function \(f(x, y) = x^2y\) and also the fact that when a and b are plugged in for x and y, the answer is 6. In other words: \(f(x, y) = x^2y\) \(f(a, b) = a^2b = 6\) The problem asks for the value of f(2a,4b). First, plug 2a in for x and 4b in for y: \(f(2a, 4b) = (2a)^2(4b)\) \(f(2a, 4b) = 4a^2(4b)\) \(f(2a, 4b) = 16a^2b\) The problem already provides the value for the variables: a2b = 6. Therefore, \(16a^2b = 16(6) = 96\).
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Re: If f(x, y) = x2y and f(a, b) = 6, what is f(2a, 4b)?
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12 Aug 2018, 07:00





