It's isosceles triangle (look at the picture).
The area of the this triangle: [tex]A=\dfrac{a^2}{2}[/tex]
We have [tex]A=50[/tex]
Substitute:
[tex]\dfrac{a^2}{2}=50\ \ \ |\cdot2\\\\a^2=100\to a=\sqrt{100}\to a=10[/tex]
Use the Pythagorean theorem:
[tex]b^2=a^2+a^2\\\\b^2=100+100\\\\b^2=200\to b=\sqrt{200}\\\\b=\sqrt{100\cdot2}\\\\b=\sqrt{100}\cdot\sqrt2\\\\b=10\sqrt2[/tex]
Answer: 10, 10, 10√2
