Question

please please answer me. my school homework

Answer 1

2/7+(-9/5)
=2/7-9/5
=LCM of 7and 5 is 35 then

2/7*5/5 -9/5*7/7
= 10/35-63/35
35 is common
10- 63/35
-53/35

Answer 2

a=2/7,b=-9/5
1)a+b=a+b
2/7+(-9/5)=(-9/5)+2/7
10-63/35=-63+10/35
-53/35=-53/35
hence proved

2)a×b=b×a
(2/7)(-9/5)=(-9/5)(2/7)
(-18/35)=(-18/35)
hence proved

HOPE IT HELPS YOU....