Can you please complete your question
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:
2
Step-by-step explanation:
You would replace the x with -2x so you would end up with -2×-2 and that is 4 then minus 2 is 2.
Answer:
3 people attended the banquet
Step-by-step explanation:
The function is given as:
b = 75 + 15n where
b represents the total = 122
n represents the number of people attending = ??
If the total cost of the banquet is 122, how many people attended the banquet?
Hence,
122 = 75 + 15n
122 - 75 = 15n
47 = 15n
Divide both sides by 15
n = 47/15
n = 3.1333333333
Approximately to the nearest whole number = 3
Therefore, 3 people attended the banquet.
Answer:
(7,-3)
Step-by-step explanation:
y = -3
substitute in the first equation
3x - y^2 = 12
3x - (-3)^2 = 12
3x - 9 = 12
3x = 12 + 9
3x = 21
x = 7
coordinates of intersection (7,-3)