Question 1111406
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<pre>
Your equation is

0.06*x + 0.08*(10000-x) = 680,


where "x" is the amount of the 6% investment.


Solve for x:

0.06x + 800 - 0.08x = 680

-0.02x = 680 - 800 = -120  ====>  x = {{{(-120)/(-0.02)}}} = 6000.


<U>Answer</U>.  $6000 was invested at 6%.  The rest  $10000-$6000 = $4000 was invested at 8%.


<U>Check</U>.   0.06*6000 + 0.08*4000 = 680 dollars.   ! Correct !
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If you want more details or if you want to see other similar solved problems, 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 &nbsp;(using one equation or a system of two equations in two unknowns), &nbsp;as well as 
different methods of solution to the equations &nbsp;(Substitution, &nbsp;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 &nbsp;"<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.