2. Panjang garis singgung persekutuan dalam dua lingkaran adalah 55 cm. Panjang jari-jari kedua lingkaran masing-masing adalah 29 cm dan 19 cm. Hitunglah jarak kedua pusat lingkaran tersebut.

<p>misalkan d = Panjang garis singgung persekutuan dalam dua lingkaran</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; D = jarak kedua pusat lingkaran</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; R = jari-jari lingkaran lebih besar</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; r = jari-jari lingkaran lebih kecil</p><p>Dik: &nbsp; d = 55 cm</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; R = 29 cm</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; r = 19 cm</p><p>Dit: jarak kedua pusat lingkaran...?</p><p>Lesaian:</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;D² = d² + (R+r)²</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; = 55² + (29+19)²</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= 3.025 + 2.304</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;D² = 5.329</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;D &nbsp;= 73</p><p>jadi, &nbsp;jarak kedua pusat lingkaran = 73 cm</p><p>semoga membantu.</p>