Step 1: According to the given measurements make a right triangle diagram.



Step 2: Find the unknown length of the triangle

            NOTE: Use the Pythagoras theorem





                                 AB = 7 cm

Step 3: Find the trigonometric ratios by substituting the appropriate lengths

              \cos\ \theta=\frac{adjacent}{hypotenuse\ }=\frac{AB}{AC}=\frac{7}{25}

              \tan\ \theta=\frac{opp}{adj}=\frac{BC}{AB}=\frac{24}{7}

Suresh Tadi
How we put a = 24 at BC and b= 25 at AC
Hai Suresh, i appreciate your doubt. Conventions in triangles: Points are usually labelled with Latin capital letters such as A, B and C. Straight lines, and in particularly segments, are frequently labelled with lower case Latin letters such as a, b, and c. Right triangle: For every right-angled triangle, ABC, we use the convention that the opposite side of angle A is named "a" (segment of BC). The opposite side of angle B is named "b"(segment of AC) and the opposite side of angle C is named "c" (segment of AB).