tolong di jawab dengan cara please

p = 15 cm
l = 10 cm

Lp = (p × l) + (p × t) + (l × t)
550 = (15 × 10) + (15 × t) + (10 × t)
550 = 150 + 15t + 10t
550 = 150 + 25t
550 - 150 = 25t
400 = 25t
400/25 = t
16 cm = t