From SOH CAH TOA, we see that we need to use the cosine ration. cos (x ∘) = a d j a c e n t h y p o t e n u s e In this case we have cos (42 ∘) = y 12 Rearrange using 'change side, change ...

National 4 Trigonometric skills Calculating an angle in a right-angled triangle Trigonometry helps solve problems involving right-angled triangles using the sine, cosine or tangent ratios. SOH CAH ...