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Write the following equation in terms of a rotated x'y'-system using θ, the angle of rotation. write the equation involving x' and y' in standard form. PLEASE HELP

x^(2)+2xy+y^(2)-8x+8y=0 θ=45

1 Answer

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Answer:(y'^2)/32 - (x'^2)/32 = 1

Explanation:

Given

xy = -16

θ = 45°

x and y are rewritten in terms of x' and y' as follows:

x = x' cos θ - y' sin θ

x = x' cos 45° - y' sin 45°

x = x' √2/2 - y' √2/2

x = √2/2 (x' - y')

y = x' sin θ + y' cos θ

y = x' sin 45° + y' cos 45°

y = x' √2/2 + y' √2/2

x = √2/2 (x' + y')

Replacing in the original formula:

[√2/2 (x' - y')] [√2/2 (x' + y')] = -16

2/4 (x'^2 - y'^2) = -16

(x'^2)/2 - (y'^2)/2 = -16

(y'^2)/32 - (x'^2)/32 = 1

Which is the standard form of a hyperbola.

User Finley Smith
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