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Scrat [10]
3 years ago
10

If 2x + 5y = 21 and x + y = 3, then what is the solution

Mathematics
1 answer:
Viefleur [7K]3 years ago
8 0
2x+5y=21, x+y=3
y=3-x
2x+5y=21
2x+5(3-x) =21
2x+15-5x=21
2x-5x+15=21
-3x+15=21
-3x=21-15
-x=6/3
-x=2
x=-2

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Step-by-step explanation:

Starting at the same point at the same time, Samuel and Heather rode their bikes in the same direction

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- Subtract the distance of Samuel from the distance of Heather

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∴ x = 37

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∵ x + 3 represents Samuel's speed

∴ Samuel's speed = 37 + 3 = 40 km/h

Samuel was going with 40 km/h and Heather was going with 37 km/h

Learn more:

You can learn more about the equation of motion in brainly.com/question/568302

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