It's important to do the same thing to both sides in an equation so it stays equal,
so first you group like terms (x with x and #'s with #'s)
so
2x+5x+3x+20=95+25
10x+20=120
subtract 20 from both sides
10x=100
divide both sides by 10
x=10
304
- 217
= 87
Difference between 304 and 217 = 87
That is SUPER blurry but I think the top question says 71/9? First, how many times does 9 go into 71? 7 times. 9*7=63. 71-63=8 The mixed number is then : 7 8/9
10:10,20,30,40,50,60,70,80,90,100
15:15,30,45,60,75,90,105