Consider a right-angled triangle with an inside angle of 30° and a hypotenuse of 8cm. Calculate the length of the opposite side to the 30° angle.

Recall the trigonometry rule SOH/CAH/TOA (Silly Old Hitler Couldn't Advance His Troops Over Africa).

  1. Label:   Draw the triangle and label the sides with Hyp, Opp & Adj.
  2. Choose:  Pick which equation to use from SOH/CAH/TOA. In this case, we choose "SOH" because we want to find the opposite side
          and we are given the angle and the length of the hypotenuse.
  3. Cover:   Using the triangle form of the equation for SOH, cover up what you want to find and write down the expression of what
         you see. So opp = sin(angle) x hyp
  4. Substitute:  opp = sin(angle) x hyp then becomes opp = sin(30) x 8
  5. Evaluate: opp = 0.5 x 8 = 4cm
JL
Answered by Joshua L. Maths tutor

3465 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Simplify 3/(x+1) + (3x-9)/2 = 1, to get a quadratic equation in the format ax^2 + bx + c = 0.


Expand and simplify (x-2)(2x+3)(x+1)


Factorise 5x^2 + 20x


A curve has equation y = x^3 - 48x. The point A on the curve has x coordinate -4. Is A a stationary point?


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences