Answers:
You are investing 3000 at 8% and 5000 at 10%
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Work Shown:
x = amount invested at 8% interest
y = amount invested at 10% interest
"you have $2000 more invested at 10% than 8%" means that y = x+2000. Whatever x is, add on 2000 to get y.
Assuming we're talking about simple interest (and not compound interest), then having x dollars in an account that pays 8% annual interest will yield 0.08x dollars of interest after 1 year.
Similarly, the 10% account will get us 0.10y dollars in interest
In total, 0.08x+0.10y dollars overall is earned in interest through the two combined accounts. This is set equal to 740 as stated in the instructions.
So we have the equation 0.08x+0.10y = 740
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Plug in y = x+2000 and solve for x
0.08x+0.10y = 740
0.08x+0.10( y ) = 740
0.08x+0.10( x+2000 ) = 740
0.08x+0.10x+0.10*2000 = 740
0.08x+0.10x+200 = 740
0.18x+200 = 740
0.18x+200-200 = 740-200
0.18x = 540
0.18x/0.18 = 540/0.18
x = 3000
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Plug this into y = x+2000 to find y
y = x+2000
y = 3000+2000
y = 5000
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As a check, we see that 0.08*3000 = 240 is the amount of interest earned from the 8% account after one year. And 0.10*5000 = 500 is the amount earned from the 10% account after one year. Added together they get us 240+500 = 740 which is the proper amount of interest to have after one year. The answers have been confirmed.