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Math Challenge III Algebra Practice Question 1.25

 
 
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Math Challenge III Algebra Practice Question 1.25
by James Shi - Sunday, 7 June 2020, 12:37 PM
 

For question 1.25, I tried solving for a + b + c + d since that would give me log_2(x) + log_2(y). Then, I could combine this value into log_2(xy) and then raise 2 to that power to find xy. However, I do not know how to approach this question. Could someone help me or give me a hint?

 
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Re: Math Challenge III Algebra Practice Question 1.25
by Areteem Professor - Monday, 8 June 2020, 8:37 PM
 

What you have so far looks good. You already know that b+d=1, so the goal would be to find what a+c is.

Note that a is an integer and, since x>2, you have that a1. Since |1a|+c4=1, what can you say about |1a|? Use these to find the possible values of a. Then use those to find possible values of c in each case.