Question 1109000
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<pre>
    x +     y = 1000,     (1)
0.05x + 0.06y =   58.     (2)


From (1), express y = 1000-x  and then substitute it into (2)

0.05x + 0.06*(1000-x) = 58

0.05x + 60 - 0.06x = 58

-0.01x = 58 - 60 = -2  ====>  x = {{{(-2)/(-0.01)}}} = {{{200/1}}} = 200.


<U>Answer</U>.  $200 was invested at 5%.   The rest  $1000 - $200 = $800 was invested at 6%.


<U>Check</U>.   200*0.05 + 800*0.06 = 58.   ! Correct !
</pre>


Solved.  &nbsp;&nbsp;// &nbsp;&nbsp;I used the Substitution method to solve the system of 2 equations in 2 unknowns.


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To see many other similar solved problems on investment, look into the lesson

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/coordinate/lessons/Using-systems-of-equations-to-solve-problems-on-investment.lesson>Using systems of equations to solve problems on investment</A>

in this site.


You will find there different approaches (using one equation or a system of two equations in two unknowns), as well as 
different methods of solution to the equations (Substitution, Elimination).


Also, &nbsp;you have this free of charge online textbook in ALGEBRA-I in this site

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson>ALGEBRA-I - YOUR ONLINE TEXTBOOK</A>.


The referred lesson is the part of this online textbook under the topic "<U>Systems of two linear equations in two unknowns</U>".



Save the link to this online textbook together with its description


Free of charge online textbook in ALGEBRA-I
https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson


to your archive and use it when it is needed.