can anyone help me at all?
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Actually Welcome to the Concept of the Trigonometry.
Since we know that, Cosine of an Angle is equal to Adjacent side divided by the Hypotenuse of the triangle.
Thus we get as,
Cos 45° = Adjacent / Hypotenuse
Cos 45° =
[tex] \frac{1}{ \sqrt{2} } [/tex]
so we get as,
[tex] \frac{1}{ \sqrt{2} } = \frac{20}{x} [/tex]
so the distance between the totem pole and the ems is the shadow is x, so we get a
[tex]x \: = 20 \sqrt{2} [/tex]
x = 20(1.41)
x= 28.28 metres.