Answer:
10cm
Step-by-step explanation:
Assuming the shape is a rectangle since it's already stated that it's a parallelogram, and the area is stated, we can use the Pythagorean theorem to find the length
[tex]a^{2} +b^2=c^2[/tex], where c will be the length
isolate c
[tex]c^2=a^2+b^2[/tex]
[tex]c=\sqrt{a^2+b^2}[/tex]
substitute for a and b
[tex]c=\sqrt{8^2+6^2}[/tex]
[tex]c=\sqrt{64+36}[/tex]
[tex]c=\sqrt{100}[/tex]
[tex]c=10[/tex]