Find the value of x. if your answer is not a whole, leave it in the simplest radical form

That line means the other side is also x

remember pythagoran theorem
for legs length a and b and hypootnuse length c
a²+b²=c²

so

legs aer x and x
hyptonuse is 6

x²+x²=6²
2x²=36
divide both sides by 2
x²=18
sqrt both sides
x=(√9)(√2)
x=3√2

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