Question

Which inequality has a solid boundary line when graphed?

Oy<-x-9
Ov<1/9x+9
Oy>-1/9x
Oy more than or equal to 9x+

Answer 1

Explanation:

any inequality with an "or equal" condition.

because that means the points on the boundary line are included, and then we draw it as a solid line.

so, it seems the 4th answer is such a case.