A chemist needs 140 milliliters of a 52% solution but has only 28% and 56% solutions available. How many milliliters of each should be mixed to get the desired solution

Idon’t know how to do that

The answer would he -4,-2 because the points are just on the opposite side. since the x axis is +4 it's going to he -4 and since the y axis is -2 it stays there because whaen rotated it stays in the third quadrant