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2 years ago

3x - 4y = 18x + 3y = -7

Mathematics

1 answer:

Mnenie [13.5K]2 years ago

4 0

Answer:

x=2, y=-3

Step-by-step explanation:

x+3y+-7

move variable to the right and -3y from each side

x+3y-3y=-7-3y

x= -7-3y

3x -4y=18

3(-7-3y)-4y=18

solve for y, distribute

-21-9y-4y=18

collect like terms

-21-13y=18

move constant and change sign

-13y=18+21

add

-13y=39

divide by -13

y= -3

substitute

x=-7-3(-3)

solve

x=2

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Answer:

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Step-by-step explanation:

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Since the engine traveled a distance of 1000 metres and each turn of the wheel has 4.7124 metres, in order to calculate the number of turns the wheel made in that course we need to divide both numbers as shown below:

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3x - 4y = 18x + 3y = -7​

3x - 4y = 18x + 3y = -7