SAT Mathematics Practice Test 3

Subtracting the sides of 3y+c=5y−7
from the corresponding sides of 3x+b=5x−7 gives (3x−3y)+(b−c)=(5x−5y).
Since b=c−

1

2

, or b−c=−

1

2

it follows that (3x−3y)+

1

2

=(5x−5y).
Solving this equation for x in terms of y gives x=y−

1

4

,
Therefore ,x is y minus

1

4

Choices B, C, and D are incorrect and may be the result of making a computational error when solving the equations for x in terms of y