Free market: supply and demand graph

I need to graph this question out to obtain further information to answer the rest of the question.

*Free market. *The equations *S=*5000+200*x *and *D=*9500-100*x *express the supply *S *and the

demand *D*, respectively, for a popular compact disc brand in terms of its price *x *(in dollars).

**a) **Graph the equations on the same coordinate system.

**b) **What happens to the supply as the price increases?

**c) **What happens to the demand as the price increases?

**d) **The price at which supply and demand are equal is called the *equilibrium price*. What is the equilibrium

price?

To find the graph, can I rewrite this in a slope-intercept form? For example, would I assume 'S' and 'D' really are 'y', then work the problem in a slope-intercept form from there?

Thank you in advance for your assistance.