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3 years ago

Subtitute 2x+y=7 and 3x-y=8

Mathematics

1 answer:

iogann1982 [59]3 years ago

8 0

Answer:

x = 3 , y = 1

Step-by-step explanation:

2x + y = 7

3x + y = 8

solution

2x + y = 7-----------(1)

3x - y = 8------------(2)

from equation 1

2x + y = 7

y = 7 - 2x-------------(3)

substitute equation 3 into equation 2

3x - y = 8

3x - (7 - 2x) = 8

3x - 7 + 2x = 8

3x + 2x = 8 + 7

5x = 15

divide through by the coefficient of x

5x/5 = 15/5

x = 3

to find y

substitute x into equation 1

2x + y = 7

2(3) + y = 7

6 + y = 7

y = 7 - 6

y = 1

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3 years ago

5. Daniel arrives at his campsite out of breath from his swim and jog. His sister tells him that he should have swam to the boat

frosja888 [35]

Answer:

hello your question is incomplete attached below is the complete question

answer :

Daniels sister is not correct because the time that will be taken by Daniel will be greater than the initial total time taken by Daniel.

Step-by-step explanation:

First determine the time it will take Daniel to reach the Boat and the jogging time

time = distance / rate

where distance can be calculated using this equation: sin 53° = 400 / x

hence x ( distance ) = 500 ft

rate = 150

therefore Time ( t ) to reach boat = 500 / 150 = 3.33 minutes

Time for jogging ( as calculated ) = 3.69 minutes

therefore total time taken by Daniel = 3.33 + 3.69 = 7.02 minutes

Finally determine if Daniel's sister is correct that he should have swam to the boat ramp and then jogged

lets assume Distance to swim = x ( according his sister )

determine the value of x = $\sqrt{400^2 + 1400^2 }$ therefore X = 1456.02 feet

∴

Total time to be taken if Daniel follows his sister's instruction = 1456.02 / 150 = 9.71 minutes

Daniels sister is not correct because the time that will be taken by Daniel will be greater than the initial total time taken by Daniel.

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3 years ago

Help please I will give brainlist

pogonyaev

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Step-by-step explanation:

perpendicular slope is a negative reciprocal of the x

which is 2x

then use the formula

y-y1 = m(x-x1)

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