Question

Need help!
the system of equations is coincident. what are the missing values?
3x+y=7
9x+___ y=___

Answer 1

coincident means they are equal.

the 2nd one has a 9x therefore the ratio is 1:3

9x+3y=21<<<missing equation

Answer 2

Ratio of coefficients are equal
Ratio of x - coefficients = 9/3 =3
Ratio of y - coefficients = y-coefficient of second equation/1 =3
y-coefficient of second equation=1*3=3
Ratio of constants = constant of second equation/7 =3
constant of second equation =3*7 = 21
The second is 9x + 3y =21
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