Answer:
15x +6y = 21. is equal to 0
7x +6y = -3. is equal to 0
Explanation:
15x +6y = 2 is equal to 0 because when we move the constant to the left and divide both sides of the equation by 3 we get:
5x + 2y - 7 = 0
Same with 7x +6y = -3, when we move the constant to the left and sum the two opposites equal to 0 it give us:
7x + 6y + 3 = 0