Write an expression to represent how much shorter the base is compared to the side: 4x + b is the base and ax + 9 is the side, it's a triangle btw

An unknown number x is at most 10. which graph best represents all the values of x? number line graph with closed circle on 10 and shading to the right. number line graph with open circle on 10 and shading to the right. number line graph with open circle on 10 and shading to the left. number line graph with closed circle on 10 and shading to the left.