-8,10 because it crosses the y axis
1. 4x = 7(x - 3) 1.Given
4x = (7)(x) + (7)(-3)
2. 4x = 7x - 21 2.Distributive property
4x - 7x = 7x - 7x - 21
3. -3x = -21 3.Subtraction property of equality
-3x : (-3) = -21 : (-3)
4. x = 7 4.Division property of equality
The answere should be 7.16
So, 672 miles divided by 56 miles per hour = 12 hours