ABC is a right-angled triangle (B being the right angle). Is AB=12 and BC=9, What is Angle A? (3.s.f.)

If you having trouble visualising it, try drawing a diagram. Start with SohCahToa. As A is opposite side BC=9, Opposite =9 As AB=12 is adjacent to A, Adjacent=12 Both opposite and adjacent are both featured in Toa. Toa stands for Tan(angle)=opposite/adjacent so Tan(angle)= 9/12 To get the angle by itself you use the inverse of tan (which looks like this on your calculator), tan^-1 (9/12) This should give you the answer of 36.8698765.... However, this should be reduced to 3 significant figures = 36.9 degrees (3.s.f.)