Won the championship lightly, in the seventh grade, the second volume of mathematics (People's Education Edition), 65 pages, choose the answer to fill in the blanks.
1、y=3x+5(x+4)
2 、{7x+4y=560 3 、{x=23y-90
9x+6y = 680 x = 18y+ 1 10
4、3:5 5、8
6、C 7、B 8、B 9、B 10、B