Question

If a + b = 12, b + c = 19, and c + a = 13, then what is the value of a + b + c?

Answer 1

hey mate!!

here's ur answer dear:-)

a+b=12———-(1)

b+c=19———(2)

c+a=13———-(3)

From (1),

b=12-a ——- putting this in (2),

12-a+c=19

or, -a+c= 19–12

or, c-a=7————-(4)

(3) + (4), we get,

c+a+c-a=13+7

or, 2c= 20

or, c=10 ———- —————————-(5)

from (4),

10-a=7

or, -a=7–10

or, -a=-3

or, a=3——————————————(6)

putting in (1),

3+b=12

or, b= 12–3=9 ———————————-(7)

From (5), (6), (7),

a+b+c= 10+3+9 = 22 (ans)

hope it helps

Answer 2

$a + b = 12 \\ b + c = 19 \\ >> c - a = 7 \\ c + a = 13 \\ > > c = 10 \\ a = 3 \\ b = 9$
Hope it will help u... :))