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puteri [66]
3 years ago
14

Person 1 can do a certain job in twenty-one minutes, and person 2 can do the same job in twenty-eight minutes. When completing t

he job together, which expression would be used to represent the amount of work done by person 1?
a. 21
b. 1/21
c. x/21
d. 21x
Mathematics
1 answer:
eimsori [14]3 years ago
7 0

The <em>correct answer</em> is:


C) x/21


Explanation:


Since Person 1 can complete the entire job (100% = 1/1 = 1) in 21 minutes, this person can complete 1/21 of the job per minute. This is Person 1's rate. If x is the amount of time it takes both people together to finish the job, then the amount of work Person 1 does would be (1/21)(x) = x/21.

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Y=mx+b is used for what math equation
soldier1979 [14.2K]
       y = m x + b is a linear equation. 
      This equation is in the slope - intercept form, where m is the slope and b is y - intercept.
       For example: y = 2 x + 5
       In this equation: m = 2 ( the slope ) and b = 5 ( the line intercepts y-axis at the point ( 0, 5 )  ).
3 0
3 years ago
Read 2 more answers
Which is an equation of the line that goes through the points ( 4, 1) and
Aloiza [94]

Answer:

  none of the above

Step-by-step explanation:

You can try the points in the equations (none works in any equation), or you can plot the points and lines (see attached). <em>You will not find any of the offered answer choices goes through the given points</em>.

___

You can start with the 2-point form of the equation of a line. For points (x1, y1) and (x2, y2) that equation is ...

  y = (y2 -y1)/(x2 -x1)·(x -x1) +y1

Filling in the given points, we get ...

  y = (3 -1)/(2 -4)·(x -4) +1

  y = 2/(-2)(x -4) +1 . . . . . simplify a bit

  y = -x +4 +1 . . . . . . . . . simplify more

  y = -x +5 . . . . . . . . . . . slope-intercept form

5 0
2 years ago
Find the first term of the sequence 4, 12, 36, 108.... which exceeds 20,000.
Schach [20]

Answer:

43740

Step-by-step explanation:

its an exponential factor of 3 just multiply each answer by 3 to get the next one up

5 0
3 years ago
PLEASE HELP DUE NOW!!!<br> WILL MARK BRAINLIEST!!!
Ulleksa [173]

Answer: -10, 10

Step-by-step explanation:

first lets add the two equations. add the x's, add the y's, add the constants on the right.

we get

0x - 1y = -10

so then divide --10 by -1 because we do the opposite operations to both sides

and we get y = 10

now substitute y = 10 into the first equation

-10x - 9(10) = 10

and then we get -10x - 90 = 10

now add 90 to both sides

-10x = 100

divide 100 by -10

x = -10

y = 10

checks out

EPIC. STAY EPIC AND AWESOME FRIEND.

3 0
2 years ago
How much water should be added to 3 gallons of pure acid in order to obtain the 15% acid solution? HELP DUE BY TOMMOROW MORNING
Pani-rosa [81]
3 gallons of acid = 100% concentration acid
? (water+acid) gallons = 15 concentration acid

Note: Every gallon of water added reduces the percentage concentration of acid. Therefore, the relationship is inverse proportionality.

Solution:

Total number of gallons (water+acid) = (3*100)/15 = 20 gallons
Therefore, gallons of water = 20-3 = 17 gallons
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3 years ago
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