There are two coefficients, one for x and one for y. The constant term may also be considered to be a coefficient. To find them we need to expand the brackets or parentheses.
2/7-x/7+5/4-y/4. The x coefficient is -1/7 and the y coefficient is -1/4. The constant is 2/7+5/4=8/28+35/28=43/28.