Kakak bantu matematika saya

(3a)² + (4a)² = 10²
9a² + 16a² = 100
25a² = 100
a² = 100/25
a = √4
a = 2

panjang = 4a = 4 × 2 = 8 m
lebar = 3a = 3 × 2 = 6 m

Keliling tanah
= 2( panjang + lebar )
= 2( 8 + 6 )
= 2 × 14
= 28 m