What is the value of k?
k = ?
k = ?
What is the value of k?
k = ?
\(m^2=4^2+8^2=16+64=80\\ m=\sqrt{80}=4\sqrt5\\\\\\ 4^2+k^2=l^2\\ l^2+(4\sqrt5)^2=(8+k)^2\\\\ k^2=l^2-16\\ l^2=64+16k+k^2-80=k^2+16k-16\\\\ k^2=k^2+16k-16-16\\ 16k=32\\ \boxed{k=2}\)
From triangle LNO:
m² = 4² + 8²
m² = 16 + 64
m² = 80...............(a)
From triangle MNO
l² = k² + 4²
l² = k² + 16..........(b)
From triangle LNM
m² + l² = (k + 8)² Recall: m² = 80, (b)
80 + k² + 16 = k² + 16k + 64
k² - k² - 16k = 64 - 80 -16
-16k = -32
k = -32/-16
k = 2