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:
x = 8
Step-by-step explanation:
Using the sine or cosine ratio in the right triangle and the exact value
sin30° = , then
sin30° = = = ( cross- multiply )
x = 8
Answer:
2 t-shirts ; 1 collar shirt
Step-by-step explanation:
We need to first obtain the ratio of T - shirts to collar shirts :
T - shirts = 10
Collar shirts = 5
Ratio = T - shirts / Collar shirts = 10 / 5 = 2 /1 = 2:1
Hence, using the ratio obtained ; if Jake buys 3 new shirts :
Number of T-shirts :
(Ratio of t-shirts / total ratio) * new t-shirts
2/3 * 3 = 2 t-shirts
Collar shirts :
1/3 * 3 = 1
2 t-shirts ; 1 collar shirt
The answer to the problem is
y=1/2x