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3 years ago

If the value of y varies directly with x and y=-1 when x=3, find y if x=9

Mathematics

1 answer:

steposvetlana [31]3 years ago

4 0

1.If y varies directly with x

Introduce the constant term k

2.y=kx

where k is the constant term

substitute the value of x and y to form the law

-1=3k

k=-1\3

:y=-1\3x....is the law

To find the value of y when x is 9

Reinstate the law which is y=-1\3x and substitute the value of x to find y

y=-1\3*9

y=-3

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Answer:

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Step-by-step explanation:

We need to find the correct representation of the inequality 'minus 32X -5 less than 52 minus X'

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So,

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Dividing both sides by -31.

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3 years ago

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3 years ago

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nignag [31]

Answer:

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Step-by-step explanation:

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Jack invested some money in a bank at a fixed rate of interest compounded annually. The equation below shows the value of his in

pochemuha

Answer:

The average rate of change of Jack's investment from the third year to the fifth year is $6.43

Step-by-step explanation:

The function that defines the value of his investment after x years,

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Which expression best represents the difference between triple a number and double a number

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