9) Because the total number of pencils is 180 and you will use them up in 30 days, the equation will have to equal 0 total pencils when 30 is substituted in for the time factor, or x. This already takes our choice 3 because it doesn’t meet this criteria.
The answer to how many pencils in 20 days could be answered by plugging in 20 for x. Choice 4 cannot work because it results in a negative number of pencils. Choices 1 and 2 use the same equation, so by plugging in 20 it is clear choice 2 is the correct answer.
10) A line parallel to the go en equation would have the same slope, -3, which means choices 1 and 4 are out. Plug in (-2,5) into both choices 2 and 3. Plugging -2 into x in choice 2 gives -5, and in choice 3 gives 5 for the y value. Therefore choice 3 is correct.
5.5-3b = 2b-6.25
5.5+6.25 = 2b+3b
11.75 = 5b
11.75/5 = 5b/5
2.35 = b
Answer:
4.5 mph or 9/2 mph
Step-by-step explanation:
Let x be the rate of the current
Formula: Distance = rate x time
where rate upstream =(12-x) and time =2 hours
15=(12-x)(2)
15=24–2x
2x=24–15
2x= 9
x=9/2=4.5 miles per hour (rate of current)
Answer:
-9, 9.7
Step-by-step explanation:
