Luas=154cm2, r=?,d=?,Kell=?

Luas keliling

pi x r²     = luas
22/7 x r² = 154
r² = 154 x 7 : 22
r² = 49
r = √49
r = 7 cm

d = r x 2
   = 7 x 2 
   = 14 cm

Keliling = pi x d
            = 22/7 x 14
            = 44 cm

Semoga membantu

keliling
= 2 x phi x r
= 2 x 22/7 x 7
= 2 x 22
= 44