X-20 = Y+20........ X-Y = 20+20........
X-Y = 40
AND
2Y-44=X+22............. Y-X= 44+22
Y-X=66
NOW, LET'S FIND X AND Y FROM THESE TWO EQUATIONS....
X-Y =40
Y-X= 66
IF WE COLLECT ....... 2Y = 106 AND Y = 53
THEN, USE Y IN ANY EQUATIONS FOR FINDING X
X-53 = 40 ..... X= 53+40 .......... X= 93
X= 93
Y=53
=3
The absolute value of any number is ALWAYS positive. Negatives get changed to positives.
5-2=3
He can only pick 7 different groups because 2 times 7 is 14, and there are 15 people in all.
Hope this helps. c: