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Question
Solve the following pairs of equations:
y - x = 0.8
`(13)/(2(x + y)) = 1`
Solution
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).
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