Tolong di jawab yang nomor 5

a)
PR² = RQ² - PQ²
16² = (y + 4)² - y²
256 = y² + 8y + 16 - y²
256 = 8y + 16
8y = 256 - 16
8y = 240
y = 240 / 8
y = 30

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b)
Luas segitiga = 1/2 x PQ x PR
                      = 1/2 x 30 cm x 16 cm
                      = 30 cm x 8 cm
                      = 240 cm²

A. 16 + y + (y + 4)
= 16 + y + y + 4
= 16 + 2y + 4
= 20 = 2y
y = 20/2
y = 10

B. 1/2 x RP x PQ
= 1/2 x 16 x 10
= 8 x 10
= 80 cm²

maaf ka kalau ribet/salah :)