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HELP
Two equations are given below:

a − 3b = 9
a = b − 3

What is the solution to the set of equations in the form (a, b)?

(−9, −6)
(−4, −3)
(−6, −3)
(−9, −7)

Respuesta :

chudung1976
a − 3b = 9
a = b − 3
we replace a=b-3 for this equation a − 3b = 9 and we have (b-3)-3b=9
or b-3-3b=9
and -2b=9+3
or -2b=12
and we have b=12:(-2)= -6
and a=b-3= -6-3= -9

The answer is (−9, −6)

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