#### Answer

$\{(5,0)\}$

#### Work Step by Step

1. Express $x$ from the first equation (solve for x).
$3x-7y=15\quad/+7y$
$3x=15+7y\qquad/\div 3$
$x=\displaystyle \frac{15+7y}{3}$
2. Substitute $x$ in the other equation and solve.
$3\displaystyle \cdot\frac{15+7y}{3}+7y=15$
$15+7y+7y=15\qquad/-15$
$14y=0\qquad/\div 14$
$y=0$
3. Back-substitute into the expression of $x$ (step 1).
$x=\displaystyle \frac{15+7(0)}{3}=\frac{15}{3}=5$
4. Write the solution as an ordered pair.
Solution set: $\{(5,0)\}$