Answer:
ab = 1
Step-by-step explanation:
A Reciprocal of a number is a number which when multiplied by the original number yields the multiplicative number, 1.
So the reciprocal of x would be x⁻¹ or ¹⁄ₓ
The information we are given states that the sum of the two non-zero numbers a and b equals the sum of their reciprocals. 
So we can write this into an equation and solve,
(See image)
Once we solve, we get the equation (ab-1)(a+b) = 0
We are given info that a+b≠0
So for the above equation to be true, ab-1 has to equal 0
For <em>this</em> to be true, the product ab must equal 1
 
        
             
        
        
        
1/3 of 30 would be 10. So 10 students walk to school.
        
             
        
        
        
Sin x = b/c
Cos x = a/c
Tan x = b/a
        
             
        
        
        
Answer:
If an object on Mercury weighed 25lb, it would weigh 75lb on Earth
(25 * 3 = 75)
The answer is b  
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