Given (x-2)2 + (y+3)2 = 81
Write in general form
Write in transformational form
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Changing General form to Standard Form
COMPLETE THE SQUARE
Step 1: Collect the x terms and y terms together. Put
brackets around them. Move the number to the other side.
Step 2:Complete the square for each variable. Divide the
middle term by two then square it.
Step 3: Balance the equation (Add the square to the other
side.
Step 4: Factor each perfect trinomial square.
Step 5: Rewrite each in standard form.
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Find the centre and the radius
x2 + y2 + 14x - 20y + 28 = 0
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Sketch:
x2 + y2 + 10 x = 0
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4. Write the mapping notation for a circle with the
equation: x2 + y2 + 12x - 8y - 35 = 0
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a) x2+y2-4x-4y-6=0
b) x2+y2-10x-11=0
Write the centre and the mapping.
Write in standard and transformational form.
c) x2+y2+6x-30=0
d) x2+y2-8x-2y=0
e) x2+y2+6x-4y-12=0
f) x2+y2+6x+4y+9=0
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