Answer: a and c
Step-by-step explanation:
7/8
3/10 of 7/8 means 3/10 times 7/8=21/80
1hour=60mins
60 times 21/80=1260/80=15.75
answer is 15.75 mins
Answer:
6x² – 10y² + 2xy + 10
Step-by-step explanation:
We'll begin calculating the sum of
x² + 3y² – 6xy and 2x² – y² + 8xy + 8
This can be obtained as follow:
... x² + 3y² – 6xy
+ 2x² – y² + 8xy + 8
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3x² – 2y² + 2xy + 8
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Next, we shall determine the sum of:
–3x² + 4y² + 3 and 4y² – 5
This can be obtained as follow:
–3x² + 4y² + 3
+ 4y² – 5
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–3x² + 8y² – 2
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Finally, we shall subtract the sum of:
–3x² + 4y² + 3 and 4y² – 5
from the sum of:
x² + 3y² – 6xy and 2x² – y² + 8xy + 8
This can be obtained as follow:
.. 3x² – 2y² + 2xy + 8
– (–3x² + 8y² – 2)
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6x² – 10y² + 2xy + 10
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Answer:
(3,-1)
Step-by-step explanation:
So we have the system of equations:
As directed, add straight down. The y-variable will cancel:
Now, divide both sides by 5. The left cancels:
So x is 3.
Now, substitute 3 for x in either of the equations:
Substitute 3 for x:
Multiply:
Subtract 9 from both sides:
So, our answer is: x=3, y=-1 or (3,-1).
And we are done :)
