If (frac{1}{2})x + 2y = 3 and (frac{3}{2})x and (frac{3}{2})x – 2y = 1, find (x + y)
-
A.
3 -
B.
2 -
C.
1 -
D.
5
Correct Answer: Option A
Explanation
(frac{1}{2})x + 2y = 3……(i)(multiply by 2)
(frac{3}{2})x – 2y = 1……(ii)(multiply by 2)
x + 4y = 6……(iii)
3x – 4y = 2…..(iv) add (iii) and (iv)
4x = 8, x = (frac{8}{4}) = 2
substitute x = 2 into equation (iii)
x + 4y = 6
2 + 4y = 6
4y = 6 – 2
4y = 4
y = (frac{4}{4})
= 1(x + y)
2 + 1 = 3