Answer:
1) 3x - 15y = 5
2) 6x - 21y = 7
Explanation:
standard form: Ax + By = C
1) y = 1/5x + 1/3
multiply each side by 15 to eliminate fractions: 15y = 3x + 5
final form: 3x - 15y = -5
2) y = 2/7x - 1/3
multiply each side by 21 to eliminate fractions: 21y = 6x - 7
final form: 6x - 21y = 7