



 
Hi Lisa, Here is a similar problem that will show you how to approach your problems.
There are two unknown numbers so let one be x and the other y. The two facts then become
You want one equation in one unknown and you have two equations in two unknowns. Since x  y = 4 adding y to both sides gives x = y + 4. Substitute this into the second equation to get
which simplifies to
The challenge is then to factor this quadratic. A little experimentation with the divisors of 165 gives me
Thus y^{2} + 4y  165 = 0 has solutions y = 11 and y = 15. Since we want y to be positive we have y = 11. Now from the first equation, x  y = 4, if y = 11 then x must be 15. Hence the two numbers are 11 and 15. Now try your problems,  


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