Answer:
x=-5, y=-8. (-5, -8).
Step-by-step explanation:
-x+2y=-11
5x-8y=39
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5(-x+2y)=5(-11)
5x-8y=39
---------------------
-5x+10y=-55
5x-8y=39
--------------------
2y=-16
y=-16/2
y=-8
-x+2(-8)=-11
-x-16=-11
-x=-11+16
-x=5
x=-5
Answer:
a) 0.4164
Step-by-step explanation:
Mean lifespan (μ) = 18.8 days
Standard deviation (σ) = 2 days
For any given lifespan 'X', the z-score is:

For X=12.04 days:

A z-score of -3.38 falls in the 0.036-th percentile of a normal distribution.
For X=18.38 days:

A z-score of -3.38 falls in the 41.68th percentile of a normal distribution.
The probability that a butterfly lives between 12.04 and 18.38 days is

Answer: multiply 631.6 by 0.8 = 505.28
Answer:
$11
Step-by-step explanation:
5*2=10 (for 5 yards) plus 1.00 for the 1/2 yard