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Information Given In Words In An Explicit Way
Examples:
[1] the shape is a square
[2] the co-ordinates of a point are (2.3)
[3] Point A is due North of Point B
These are all easy to spot and to change from written form
to diagramatic form.
Information NOT Given In Words In SUCH An Explicit Way
Sometimes we do not seem to have enough information to proceed with the question
but we know that it must be there and that we are not spotting it.
Example
Find the
the equation of the circle
with centre (3,4)
and which touches the x-axis
STEP 1
Draw the axes and mark the given point.
STEP 2
Use the information that the circle touches the x-axis.
Since it touches rather than crosses then the touch must be directly below the given point.
STEP 3
Show the co-ordinates of the point where the circle touches the x-axis.
STEP 4
It is now easy to calculate the radius of the circle.
Radius = the difference between the y co-ordinates
Radius = 4 - 0
Radius = 4
STEP 5
Use the co-ordinates of the centre of the circle and the radius
to find
the equation of the circle
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