Answer:
2
Step-by-step explanation:
m² = 4² + 8²
m² = 16 + 64
m² = 80
l² = k² + 4²
l² = k² + 16
m² + l² = (k + 8)² m² = 80, (b)
80 + k² + 16 = k² + 16k + 64
k² - k² - 16k = 64 - 80 -16
-16k = -32
k = -32/-16
k = 2
