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Math·Algebra·Systems of two linear equations in two variables

hard

$2x+5y=9$
$12x+30y=54$
For each real number $r$, which of the following points lies on the graph of each equation in the $xy$-plane for the given system?

A

$(r,-\frac{2r}{5}+\frac{9}{5})$

B

$(-\frac{2r}{5}+\frac{9}{5},r)$

C

$(-\frac{2r}{5}+9,\frac{2r}{5}+54)$

D

$(\frac{r}{6}+9,-\frac{r}{6}+54)$