In the linear equation y = mx + b, y-intercept represents the value of y. It is the point where the line crosses the y-axis(vertical axis)
Finding the y-intercept is done by looking at which point in the graph crosses the y-axis. This point will always have an x-coordinate of zero(0).
The lowest common denominator for 15 and 12 will get in this way
15=3*5
12 = 3*4
LCM will be 3*4*5=12*5=60
27 vehicles
3/5 x 45
5 goes into 45 9 times, 9x3= 27, therefore there are 27 minivans