Question

Trigonometry help me pls!!

Answer 1

let the unknown angle be a

so a+90 + 20= 180

If we take 70°,then area (A)=

`(1)/(2) sin70xy`

If we take 90° then area(A)=

[tex] \frac{1}{2} sin90x \times 10 = \frn

therefore y=10.64 cm

By using pythagoras theorem

y^2=x^2+10^2

or, x^2=y^2-100

or, x^2=10.64^2-100

or,x^2=13.2096

or, x= 3.63 cm