Question

I really need help please!

Answer 1

As we know that angle of semi circle is 180°.

Here,

FLG = 40°

GLH = ?

HLJ = 60°

FLG + GLH + HLG = 180°

40° + GLH + 60° = 180°

GLH + 100° = 180°

GLH = 180° - 100°

GLH = 80°

Now,

FLH = 40° + 80° = 120°

`\sf \: Length \: of \: an \: arc \: of \: GHF = ( \theta)/(360) * 2 \pi \: r`

`= \frac {120}{360} * 2 * (22)/(7) * r`

`= (1)/(3) * (44)/(7) * r`

`= (44)/(21) * r`

`= 2.09r`