Question

a+b+c = 90 , a-b-c = 30 find value of a b and c.

Answer 1

Let the value of a, b and c = x
So,
x + x + x = 90
3x = 90
x = 90/3
x = 30

So, a = 30
b = 30
c = 30

Or,
30 - 30 - 30 = 30
30 = 30

HOPE IT HELPS YOU...

Answer 2

a+b-c=90. .....(1)
a-b-c=30. .....(2)
on adding
2a=90+30
2a=120
a=120/2
a=60
putting the value of a in 1 and 2 we get
b-c=30. .....(3)
b+c=30
on adding we get
2b=60
b=60/2=30
putting the value of b in (3) we get
30+c=30
c=30-30=0

hence a= 60
b= 30
c=0