Answer:
57.09
Step-by-step explanation:
It's the factor theorem.
P(-4)
Equal to 0
Ring ding ding ding ding ding ding ding it’s 4/5
Answer: This coil will not be enough to complete the job.
Step-by-step explanation:
The circumference of the coil of wiring can be calculated with:

Where r is the radius and 
The radius can be calculated by dividing the diameter by 2. Then:

Convert 9 inches to yards (1 yard=36 inches):

Substitute this radius into the formula:

Since there are 21 circles of wire, you need to multiply
by 21:

The coil has 32.97 yards of wire and Alex needs 34 yards, therefore, this coil will not be enough to complete the job.
Answer:
112.5
Step-by-step explanation:
you would then cross multiply. 90 x 100 and 80 x ?
you will then have 9000 = 80?
divide 9000 by 80 and you will get ? = 112.5
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