Question

Solve the following pairs of equations:
y - x = 0.8

`(13)/(2(x + y)) = 1`

Answer 1

The given equations are
y - x = 0.8
-x + y = 0.8     ....(i)
And, `(13)/(2(x + y)) = 1`
⇒ 13 = 2x + 2y
⇒ 2x + 2y = 13   ....(ii)
Multiplying eqn. (i) by 2, we get
-2x + 2y = 1.6   ....(iv)
Adding eqns. (ii) and (iii), we get
4y = 14.6
⇒ y = 3.65
Substituting the value of y in eqn. (i), we get
-x + 3.65 = 0.8
⇒ -x = -2.85
⇒ x = 2.85
Thus, the solution set is (2.85, 3.65).