Jawaban:

6. d.144cm²

7. b.24cm

8. c.270cm²

9. c. 46cm

10. 39m

Penjelasan dengan langkah-langkah:

6. luas persegi panjang

= S × S

= 12 × 12 = 144 cm²

7. luas segitiga = 1/2 × a × t

84cm² = 1/2 × a × 7

84cm² = 1 × a × 3,5

a = 84 ÷ ( 1 × 3,5 )

a = 84 / 3,5 = 24cm

8. luas gabungan = ( luas persegi ) + ( luas segitiga )

= ( S × S ) + ( 1/2 × a × t )

= ( 15 × 15 ) + ( 1/2 × 6 × 15 )

= 225 + 45 = 270cm²

9. luas persegi panjang= P × L

120 = P × 8

120/8 = P

P = 15

Keliling persegi panjang

= 2 × ( P + L )

=2 × ( 15 + 8 )

= 2 × 23

= 46cm

10. Keliling Segitiga

= A + B + C

= 12 + 14 + 13

= 39m