3 problems...

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3 problems...

by scmetzger » Mon May 18, 2009 10:36 am
I did a practice yesterday and I got those three problems wrong but I just don't know how to do them. I will provide the correct answers but please show me how to solve these problems. Thanks you.

1. If the speed of x meters per second is equivalent to the speed of y kilometers per hours, what is y in terms of x?

Answer: 18x / 5

2. If xy=1, what is the value of 2^(x+y)^2 / 2^(x-y)2?

Answer: 16

3. For which of the following functions if f(a+b)=f(a) + f(b) for all positive numbers a and b?

Answer= -3x
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by Neo2000 » Mon May 18, 2009 2:31 pm
1.Convert km/hr to m/s
X m/s = Y (km/hr) = Y (1000/(60 x 60) ) m/s

Simplify :)

2. This is of the form (a^m)/ (a^n) = a^(m-n)

(x+y)^2 - (x-y)^2 = 4xy

Simplify