Higher Maths - Equation of a tangent to a circle

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Schoolwork123
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#1
Report Thread starter 4 days ago
#1
Hi - any ideas how I might answer this textbook question?

The circle with equation x^2 + y^2 - 10x - 14y + 29 = 0 has two tangents with gradient 2. Find the points of contact of the circle and these tangents and hence find the equations of both tangents.

The answers are:
(-1, 10); (11, 4)
y = 2x - 18; y = 2x + 12
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yumyum112358
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#2
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#2
Is this GCSE-
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Schoolwork123
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#3
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#3
This is SQA Higher - I guess the equivalent to 1st year of A-level
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the bear
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#4
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you should rearrange the circle equation into the form (x + a)2 + (y + b)2 = r2

then you can find the centre.

once you have that you can think about the equations of the radii connecting the centre to the tangent points.
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Schoolwork123
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#5
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#5
Thanks so much - just used that method and finally managed to get the correct answer
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