Question

Final question guys! Need this for a good grade please help me out. I need help finding this equation/

An investor bought some municipal bonds yielding 5% annually and some certificates of deposit yielding 7% annually. If her total investment amounts to $20,000 and her annual return is $1160, how much money is invested in bonds and how much in certificates of deposit?

Answer 1

Plato much?

Answer 2

.05b + .07c = 1160
b + c = 20000

Answer 3

Excuse me?

Answer 4

Ty Mramirez I am going to try and do this :) IOU

Answer 5

No problem, let me know if you get stuck

Answer 6

Well I am wondering How will I solve for b and c?? I am thinking about this and I havent done tthese types of problems 5 years.

Answer 7

You can use either substitution or elimination for this 2x2 linear system.

Answer 8

I would probably use substitution because you can get a variable alone by itself

Answer 9

b + c = 20000
-c -c
b=20000 - c

insert that into the other equation

Answer 10

.05(20000 - c) + .07c = 1160

Answer 11

Ok that clears things up a ton more.

Answer 12

How do i get the 2cs combined or dont i?

Answer 13

.05(20000 - c) + .07c = 1160
1000-.05c + .07c = 1160
1000 + .02c = 1160
-1000 -1000
.02c=160
/.02 /.02
c=8000

Answer 14

Insert c into the other equation to solve for b

Answer 15

b + 8000 = 20000

Answer 16

I found that equation just as you submited. You are an awesome help. I found a useful link
http://www.purplemath.com/modules/systlin4.htm
What i was going off of as well. Ty again mramirez :)

Answer 17

No worries, have a great day

Answer 18

You too !