34=2x + 16
18=2x
x=9
Robert used 9 grams of iron filings in his first experiment.
9x+ 5y=35
2x + 5y=0 |* -1
9x +5y= 35
-2x -5y= 0
-----------------
7x / = 35
x=35:7
x=5
2x+5y=0
2*5+5y=0
10+5y=0
5y=-10
y= -10:5
y=-2
Answer:
3m == 5w, that means for such unit, there is a 2 person difference
30 person difference = 30/2 = 15units
and again one unit means 3m and 5w
so 15*3men, and 15*5women
and you can check the difference is 30
The first question answer is 21*10^7
The second question answer is 5*10^2