Question

Solve the Sig system of equations

A + b = 135
A-b = -35

Answer 1

A + b = 135...............(1)
A - b = -35................(2)

Add both the equations (1) and (2)

2A = 100
A = 50

now for b, put the value of A in equation (1)

50 + b = 135
b = 135-50
b = 85

Answer 2

Hey there!

a + b = 135  (1)
a - b = - 35   (2) You use method of reduction (We add)
-------------
2a = 100
a = 100/2
a = 50

Replacements:a = 50 in (1)

a + b = 135
50 + b = 135
b = 135 - 50
b = 85

Answer:
a = 50
b = 85