Hello there!
A positive slope is represented in a linear equation by a positive coefficient behind the x term. A positive slope means that the graph is on an increasing interval as x approaches +∞. In a more simple way, a positive slope means that the graph is going up from left to right. 
A negative slope is represented in a linear equation by a negative coefficient behind the x term. A negative slope means that the graph is on a decreasing interval as x approaches +∞. In a more simple way, a negative slope means that the graph is going down from left to right. 
The x intercept(s) of a graph are where the graph touches the x-axis. These are also known as the zero(s) OR solution(s) of the function. 
The y intercept(s) of a graph are where the graph touches the y-axis. 
I hope this helps!
Best wishes:)