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Ray Of Light [21]
2 years ago
5

Solve the system of equations by substitution. X + y = 21 y = 6x

Mathematics
2 answers:
Inessa05 [86]2 years ago
8 0

Answer:

x=3

y=18

Step-by-step explanation:

x+y=21..........equation 1

or,x=21-y......equation 2

y=6x.......equation3

substituting the value of x in equation 3

y=6(21-y)

or,y=126-6y

or,7y=126

y=18

again,substituting the value of y in equation 2

x=21-y

or,x=21-18

x=3

x=3,y=18

eimsori [14]2 years ago
5 0

Answer:

x = 3

y = 18

Step-by-step explanation:

you replace y with 6x

x + 6x = 21

combine like terms

7x = 21

divide both sides by seven

x = 3

then you plyg 3 into the other equation

y = 6(3)

y= 18

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Answer:

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6 0
3 years ago
What is 5/2 divided by 2/5
Len [333]

Answer: 6 and 1/4

Step-by-step explanation: To solve this problem, we first leave 5/2 alone so don't do anything to it.

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The reciprocal of 2/5 is just the opposite of it when

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6 0
2 years ago
You drink a beverage with 120 mg of caffeine. Each hour, the caffeine in your system decreases by about 12%. How long until you
uysha [10]

Answer:

  19.44 hours, about 19 hours 26 minutes

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It will take about 19.44 hours, or 19 hours 26 minutes, for the caffeine level in your system to decrease to 10 mg.

3 0
3 years ago
Answer: Alex is making a clock to give to his grandfather. To make the clock, he saws a slice of wood from a cylindrical log. Wh
ss7ja [257]
It would be circular since it was cut from a cylindrical log.

Hope This Helps You!
Good Luck Studying :)
7 0
2 years ago
Read 2 more answers
VERY VERY URGENT!!!!!!!
Arte-miy333 [17]

The answer is 7/25, because cos is opposite/hypothenuse.

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3 years ago
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