Page 30 - Digital Book Bangun Datar Segitiga Kelas VII

Penyelesaian :

Gambar (i) Gambar (ii)

= ⁄ × × = ⁄ × ×
1
1
2 2
1
1
= ⁄ × 8 × 6 = ⁄ × 12 × 6
2 2
= 4 × 6 = 6 × 6
= =

Gambar (iii) Gambar (iv)

1
1
= ⁄ × × = ⁄ × ×
2 2
1
1
= ⁄ × 16 × 4 = ⁄ × 5 × 4
2
2
= 8 × 4 = 5 × 2
= =

2. Perhatikan gambar disamping. Jika  =
90°, = 4 , = 3 , dan = 5 ,
̅̅̅̅
̅̅̅̅
̅̅̅̅
tentukan
a. Luas segitiga
b. Panjang
̅̅̅̅

Penyelesaian :

Menentukan luas  Menentukan panjang
̅̅̅̅

1
= ⁄ × × = ⁄ × ×
1
2 2
1
= ⁄ × × 6 = ⁄ × 5 ×
̅̅̅̅
̅̅̅̅
1
̅̅̅̅
2 2
1
= ⁄ × 4 × 3 12 = 5 ×
̅̅̅̅
2
= 2 × 3 12 = = ,
̅̅̅̅
= 5

Digital Book Matematika SMP/MTs kelas VII
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