Question 1135632
{{{system(2p+3c=7,3p+4c=10)}}}



3*E1 and 2*E2, and then subtract.  Use this to find c.



From same system, 4*E1 and 3*E2, and then subtract.  Use this to find p.




Also notice, that in your initial system, E2-E1 will give you {{{p+c=3}}}, which you might want to use instead of either of the initial equations of the system.