3 years ago

What is the solution of the system ? Use substitution y=2x+7 y=x-1

1 answer:

5 0

(-8,-9)

Explanation:

y=2x+7 ; y=x-1

x-1=2x+7

x-1-7=2x+7-7

x-8=2x

x-x-8=2x-x

x=-8

y=x-1

y=-8-1

y=-9

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where y is the number of seconds needed to complete the reaction and x is the temperature in degrees Celsius at which the reaction occurs.

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