Trigonometry is the worst please someone answer this for me ... no links please

 Approximately 22.62 degrees

===============================================

Work Shown:

cos(angle) = adjacent/hypotenuse

cos(y) = 12/13

y = arccos(12/13)

y = 22.6198649

y = 22.62

Notes:

Arccosine is the same as inverse cosine. On your calculator there should be a button labeled Make sure your calculator is in degree modeThe decimal result for y, shown above, is approximate. I rounded to two decimal places to show the final answer. Round however you need to if your teacher instructs otherwise.