Let c and d be the number of cds and dvds respectively.
c+d=12
c=12-d
The we are told that:
2c+3d=31, using c found above in this equation gives you:
2(12-d)+3d=31
24-2d+3d=31
24+d=31
d=7
So Phillip bought 7 dvds.
check...
3*7+2(12-7)=31
21+2(5)=31
21+10=31
31=31
Hello. 10x-3-2x=4 ; 10x-2x=4+3 ; 8x=7 ; x=7/8. I hope to have helped you
3x2.7=8.1,,, im not sure this is what you were asking for but i hope it helps
XoXo
the final temperature was -2 F, and that reflects a drop of 13 units, so
-2------0------------------------------------------------------+11.
