Step-by-step explanation: The slope of a line may be found by using the equation y = mx + b, where m = the slope and b = the y-intercept (where your graph crosses the y-axis). In your above equations, we can clearly see that -5 is the coefficient of x for line A and 2 is the coefficient of x for line B. Therefore, the slope of line A is -5 and the slope of line B is 2, or answer A.
The equation shown above does not show the substitution property. Instead, it shows the Addition Property of Equation where 3 is added to both of its sides. This is shown below, 4x - 3 = 7 4x - 3 + 3 = 7 + 3 4x = 10
