Given sin(u) = Negative StartFraction 7 Over 25 EndFraction and cos(v) = Negative four-fifths, what is the exact value of cos(u-v) if both angles are in quadrant III?

You move the constant to the right side and change its sign to be 9z= -6 -8. that’s the first step.the second step would be calculate the difference of -8-6 to get -14. you equation should now be 9z=-14the last step is to divide both sides by 9 to get z=-14/9hope this