Tolong jawab no 4dan5

4. 78cm
    Keliling [tex] \frac{1}{2} [/tex] lingkaran = [tex] \frac{1}{2} [/tex] × [tex]2 \pi r[/tex]
    = [tex] \frac{1}{2} [/tex] × 2 × [tex] \frac{22}{7} [/tex] × 7cm
    = [tex] \frac{1}{2} [/tex] × 44cm
    = 22cm

    Kelililng Persegi Panjang = 2 (p+l)
    = 2 (24cm+14cm)
    = 2 (38cm)
    = 76cm
    Keliling Bangun No.4 = 22cm + 76cm = 98cm


5. Kelililng Persegi Panjang = 2 (p+l)
    = 2 (20cm + 10cm)
    = 2 (30cm)
    = 60cm

    Keliling Segitiga = a + b + c
    Cari dulu c nya
    c =  [tex] \sqrt{ a^{2} + b^{2} } = \sqrt{ 5cm^{2} + 12cm^{2} } = \sqrt{ 25cm + 144cm } = \sqrt{169} = 13cm[/tex]
    = 10cm + 12 cm + 13cm = 35cm
    Keliling bangun No.5 = 60cm + 35cm = 95cm