Which equation is in standard form?

a. 3x + 4y = 10

b. 19 + 3y = 2x

c. 7y-7x=8

d. 8 + 5x = 3y

keeping in mind that

standard form for a linear equation means

• all coefficients must be integers, no fractions

• only the constant on the right-hand-side

• all variables on the left-hand-side, sorted

• "x" must not have a negative coefficient

3x + 4y = 10.