tolong yang bisa menjawab no 20 dan 21?

20 ] Tinggi segitiga

[tex] = \sqrt{17 {}^{2} - 8 {}^{2} } \\ \\ = \sqrt{289 - 64} \\ \\ = \sqrt{225} \\ \\ = 15 \: cm[/tex]
Luas segitiga STR

= ( 1/2 × [ 15 + 8 ] × 15 ) - ( 1/2 × 8 × 15 )

= 172,5 cm2 - 60 cm2

= 112,5 cm2

Option = A

21 ] Panjang BE

[tex] \sqrt{10 {}^{2} - 8 {}^{2} } \\ \\ = \sqrt{100 - 64} \\ \\ = \sqrt{36} \\ \\ = 6 \: cm[/tex]

Panjang BC

[tex] \sqrt{17 {}^{2} - 8 { }^{2} } \\ \\ = \sqrt{289 - 64} \\ \\ = \sqrt{225} \\ \\ = 15 \: cm[/tex]

Panjang CE

= 15 cm - 6 cm

= 9 cm

Option = B

Maaf kalau membingungkan...

Maklum anak SD.☺

20)RU=√17²-8²
=√289-64
=√225
=15 cm
L RST=1/2×alas × t
=1/2×15×15
=112,5 cm² (a)
21)BC=√ 17²-8²
=√289-64
=√225
=15 cm
BE=√10²-8²
=√100-64
=√36
=6 cm
CE= BC-BE
=15-6
=9 cm (b)