Tomas wrote the equation y = 3x +y equals 3 x plus startfraction 3 over 4 endfraction.. when sandra wrote her equation, they discovered that her equation had all the same solutions as tomas's equation. which equation could be sandra's? –6x + y = negative 6 x plus y equals startfraction 3 over 2 endfraction. 6x + y = 6 x plus y equals startfraction 3 over 2 endfraction. –6x + 2y = negative 6 x plus 2 y equals startfraction 3 over 2 endfraction. 6x + 2y = 6 x plus 2 y equals startfraction 3 over 2 endfraction.