Question

Can you please explain this as if I never knew this? I’m really struggling.

Answer 1

To determine the value of cos (A) using pythagoras theorem:

Using pythagoras theorem:

`\begin{gathered} \text{Hypotenuse = 50} \\ \text{Opposite = 30} \\ \text{Adjacent = 40} \end{gathered}`
`\begin{gathered} \text{Hyp}^2=\text{opp}^2+\text{adj}^2 \\ to\text{ CONFIRM } \\ 30^2+40^2=50^2 \\ 900+1600=2500 \end{gathered}`
`\begin{gathered} Cos\text{ A = }\frac{adj}{\text{hyp}} \\ When\text{ A = angle subtends by the triangle} \\ adj=30 \\ hyp=50 \\ \text{Cos A=}(30)/(50) \\ \text{CosA=}(3)/(5) \end{gathered}`

Therefore the value of CosA = 3/5