Given that 2x + y = 7 and 3x – 2y = 3, by how much is 7x greater than 10?
-
A.
1 -
B.
3 -
C.
7 -
D.
17
Correct Answer: Option C
Explanation
2x + y = 7…(1)
3x – 2y = 3…(2)
From (1), y = 7 – 2x for y in (2)
3x – 2(7 – 2x) = 3
3x – 14 + 4x = 3
7x + 3 + 14 = 17
x = (frac{17}{7})
Hence, 7 x (frac{17}{7})
= 17 – 10
= 7