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:
square root of 14
Step-by-step explanation:
square root of 7 to the square is 7
7+7 = 14
square root of 14 can't be simpliflied
A midsegment is given by the formula:
Where x1, x2, y1, and y2 correspond to their respective coordinates. We can do the equation:
This gets us a midpoint coordinate of <span>
(1,1)</span>As for distance, it will be found by doing:
We can do the following:
This simplifies to
:)
Answer:
The value of A is 20
Step-by-step explanation:
To find the answer, note that all triangles have a interior degree measurement of 180. Set the sum of the angles equal to 180.
71x - 1 + 20x + 90 = 180
91x + 89 = 180
91x = 91
x = 1
Now we can use this in the A angle to find the value.
A = 20x
A = 20(1)
A = 20
