Answer: A; 6.3%
Step-by-step explanation:
Problem 1
For the first problem, we first want to find y so that we can plug it into the expression.
We can use elimination method for the system of equations to solve.
3x+3y=21
3x-y=5
We subtract both equations to eliminate x.
4y=16 [divide both sides by 4]
y=4
Now that we know y, we can plug it into the expression.
[divide]
[subtract]
We know that the answer is A.
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Problem 2
For the second problem, we need to know how to calculate percent error. The formula for precent error is 
. We know that the exact value is 80 because the buyer was supposed to given 80. 75 is the measured value because that was what the buyer was given.
[subtract]
[solve absolue value]
[divide]
[multiply]
Since the problem said to round to one decimal place, we know that the answer is 6.3%.
Answer:
<h2>80=5x+4y</h2>
Step-by-step explanation:
Step one:
given
let binders be x
and notebooks be y
let the total sale be T
the cost of binder is $5 each
the cost of notebook is $4 each.
the total sales expected is $80
step two:
the linear model for the total sales is given as
T=x+y
using the given data, the situation can be represented linearly as
80=5x+4y
Therefore the linear expression for the total sale is 80=5x+4y
Answer:
2 sets of possible solutions:
x=3, y = 5
and
x=-1, y = -3
Step-by-step explanation:
Using the graphical method, (see attached)
you can graph both equations and find their intersection points.
From the attached plot, you can see that the graphs intersect at (3,5) and (-1,-3)
Alternatively, you can solve this numerically by solving the following system of equations. You will get the same answer.
y = 2x + 1 ------------------- eq. (1)
y = x² - 4 ------------------- eq. (2)
Ratios are proportional if they represent the same relationship. One way to see if two ratios are proportional is to write them as fractions and then reduce them. If the reduced fractions are the same, your ratios are proportional.
Answer:
The amount that we should deposit in each bank is around $942.
Step-by-step explanation:
Case 1:
A=$1000
n = 12
t = 2
r = 3% or 0.03
p = ?
The compound interest formula is :
Substituting values in the formula;
=> 
=> 
p = $941.84
Case 2:
A=$1000
n = 365
t = 2
r = 3% or 0.03
p = ?
=> 
=> 
p = $941.76
The amount that we should deposit in each bank is around $942.
