Solve the following pair of linear equations by the elimination method and the substitution method:
$3x - 5y - 4 = 0$ and $9x = 2y + 7$

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(N/A) Given equations are:
$1) 3x - 5y = 4$
$2) 9x - 2y = 7$
Elimination Method:
Multiply equation $(1)$ by $3$ to make the coefficients of $x$ equal:
$9x - 15y = 12$ $(3)$
Subtract equation $(2)$ from $(3)$:
$(9x - 15y) - (9x - 2y) = 12 - 7$
$-13y = 5$
$y = -5/13$
Substitute $y = -5/13$ into equation $(1)$:
$3x - 5(-5/13) = 4$
$3x + 25/13 = 4$
$3x = 4 - 25/13 = (52 - 25)/13 = 27/13$
$x = 9/13$
Substitution Method:
From equation $(1)$,$3x = 5y + 4$,so $x = (5y + 4)/3$.
Substitute this into equation $(2)$:
$9((5y + 4)/3) - 2y = 7$
$3(5y + 4) - 2y = 7$
$15y + 12 - 2y = 7$
$13y = -5$
$y = -5/13$
Then $x = (5(-5/13) + 4)/3 = (-25/13 + 52/13)/3 = (27/13)/3 = 9/13$.
Thus,the solution is $x = 9/13$ and $y = -5/13$.

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