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3a3 - 5b3 + (-2)a3 + (6)b3 = a3 + b3
So -2 and 6 will be the answer.
Answer:
Variance is 123.14 square kilograms.
Step-by-step explanation:
We have been given that

Now, we know the formula,

Hence, the variance is 123.14 square kilograms.
Since y=7x we can replace the y in the second equation with 7x
-5x+14x=9
x=1
Now plug in to get 7 for y, since 7x=y
Answer: x=1, y=7