## Answer :

[tex] a^{2} + b^{2} = c^{2} 300 ^{2} + 400 ^{2} = c^{2} c^{2} =250,000 \sqrt{250,000} =500m[/tex]

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The displacement is the hypotenuse of this triangle, with sides 300m and 400m.

We can work out this distance using Pythagorus' theorem, because we know that;

[tex] a^{2} = b^{2} + c^{2}[/tex]

Where [tex]a[/tex] is the hypotenuse, and [tex]b[/tex] and [tex]c[/tex] are the two other sides. So;

[tex] a^{2} = b^{2} + c^{2} \\ \\ a^{2} = 300^{2} + 400^{2} \\ \\ a^{2} = 90000 + 160000 \\ \\ a = \sqrt{250000} \\ \\ a = \boxed{500m}[/tex]