Question 250440
x + y = 5000
x * .12 + y * .10 = 568


use first equation to solve for y in terms of x.


y = 5000 - x


substitute for y in second equation to get:


x * .12 + (5000-x) * .10 = 568


simplify by removing parentheses to get:


x * .12 + 5000*.10 - x*.10 = 568


combine like terms and simplify further to get:


.02*x + 500 = 568


subtract 500 from both sides to get:


.02*x = 68


divide both sides by .02 to get:


x = 68/.02 = 3400.


if x = 3400, then y = 5000 - 3400 = 1600.


.12 * 3400 + .10 * 1600 = 408 + 160 = 568.


his confirms the answer is good.


the answer is:


 geoff invests 3400 at 12% and 1600 at 10% to gain 568 interest in one year.