9)To find the LCD you need to find a number that all of the denominator numbers can divide into, for this problem it would be 12. 12/6+12/4+12/3=1
2+3+4=1
9=1
No solution
10) In order to solve this problem you need to cross multiply
2(3x+5)=7(10
6x+10=70
6x=60
x=10
Have a great day!:)