Find b of y = mx + b first using a modified version of the equation.
b = y - mx
b = -1 -(1.2×-3)
b = 13/5 = 2.6
y = 1.2x + 2.6 ← result of substituting values of m and b into y = mx + b
-1.2x + y = 2.6 ← result of subtracting 1.2x from both sides
12x - 10y = -26 ← result of multiplying previous equation by -10
6x - 5y = -13 ← result of dividing previous equation by 2
ANSWER: 6x - 5y = -13
