Answer:
21/29
Explanation:
Recall that the cosine ratio is the adjacent side over the hypotenuse.
From the triangle, the adjacent side to angle Θ is 42. The hypotenuse (opposite from the right angle) is 58. Therefore:
![\cos(\theta)=adj/hyp](https://img.qammunity.org/2021/formulas/mathematics/high-school/nm3zoumqzs9aw8a4a6lybzt4g24geyfgrc.png)
Substitute 42 for the adjacent side and 58 for the hypotenuse:
![\cos(\theta)=42/58](https://img.qammunity.org/2021/formulas/mathematics/high-school/zelxowxh1nfddz07l8r3wdbhmootvrkoh4.png)
Reduce:
![\cos(\theta)=21/29](https://img.qammunity.org/2021/formulas/mathematics/high-school/b8uhse8i0gpdap037c4ivcbmr68dwxmwxo.png)
And we're done!