Stan invested $13,000, part at 17% and part at 2%. If the total interest at the end of the year is $1,910, how much did he invest at 17%?
Set up a system of equations to model this situation. (That means you will need TWO different equations.)
Let x be the number of dollars invested at 17% and let y be the number of dollars invested at 2%.
Try to work with that, and let me know what you get. If you have any problems, I'm here to help.
Sorry, I am still not sure how to get started.
We are given the amount she invests. She invests part at 17% (x) and part at 2% (y). That will give us the first equation.
We are given the total interest. Total interest is the interest at 17% together with the interest at 2%. That will give us the second equation.
Try to write the equations now. (You'll be using x, y, and all the numbers in the problem. They won't all be in the same equation because we're finding TWO equations.)
anywhere close?
x+y=13000
x+y=1910
Your first equation is entirely correct (x+y = 13,000).
Your second equation is almost correct. Just add in the interest rates because it is the interest of x and the interest of y that yields the interest $1910.
So would I just put 17+2=1910? If so how do I figure the investment at 17%?
17 + 2 does not equal 1910, so you know that's not right. You've dropped your x and y. Put them back in, and you have to convert your percentages to decimals.
The investment at 17% is x, so we'll solve for that after we get our two equations.
.17x+.02y=1910
Yes, very good.
The two equation are:
x + y = 13,000
.17x + .02y = 1910
Use the substitution method of solving systems of equations. Solve the first equation for y, and then plug that into the second equation. You will have all x's in the equation now and can easily solve it.