PLEASE ANSWER PROPERLY OR I WILL REPORT AND BLOCK YOU.

162 = 182 + 192 – 2(18)(19)cos(Z)

256 = 324 + 361 – (684)cos(Z)

256 = 685 – (684)cos(Z)

–429 = –(684)cos(Z)

To the nearest whole degree, the measure of Z is
degrees.