Given:
The rate of interest on three accounts are 7%, 8%, 9%.
She has twice as much money invested at 8% as she does in 7%.
She has three times as much at 9% as she has at 7%.
Total interest for the year is $150.
To find:
Amount invested on each rate.
Solution:
Let x be the amount invested at 7%. Then,
The amount invested at 8% = 2x
The amount invested at 9% = 3x
Total interest for the year is $150.
Multiply both sides by 100.
Divide both sides by 50.
The amount invested at 7% is 
.
The amount invested at 8% is
The amount invested at 9% is
Therefore, the stockbroker invested $300 at 7%, $600 at 8%, and $900 at 9%.
Usando un sistema de ecuaciones, se encuentra que
- Cada manzana cuesta $3.
- Cada pera cuesta $1.
-----------------------
- Un sistema de ecuaciones soluciona esta pergunta.
- El custo de una manzana es x.
- El custo de una pera es y.
-----------------------
- <u>Seis manzanas y 8 peras cuestan $26</u>, o sea,
- <u>Cada manzana cuesta el triple de cada pera</u>, o sea,
-----------------------
Primero, encontramos el cuesto de una pera, substituyendo la segunda en la primera ecuación.
Cada pera cuesta $1.
-----------------------
<u>Cada manzana cuesta el triple de cada pera</u>, o sea, 
.
Cada manzana cuesta $3.
Se encuentra um problema similar en brainly.com/question/24646137
Answer:
p=-1
Step-by-step explanation:
12p - 9p --7p -8 =-18
19p-9p-8=-18
10p - 8 = -18
10p = -10
p=-1
