We are given a diagram which we are to analyze and and solve for x.
We can see the a straight line is intersected by another line thus forming two angles which are supplementary. It means that the sum of these angles is equal to 180 degree.
Rewrite the given equation as . Since , you can conclude that the imimum value of y will be gained for the minimum value of . The minimum value of is 0 for x=2. So, y(2)=0+4=4. Answer: minimum value of y is 4, when x=2.