Tag Archives: school

Parabola, it’s scarily simple…

No distances, no circles, and you can easily derive an equation.

Just a right angled triangle.

First, the definition of a parabola from the focus and directrix.

Pick a line, the directrix, and a point (B) not on that line (the focus):

parabola 1

Find the line at right angles, passing through a point (C) on that line.

parabola 3

Now find the line from B to C, and the midpoint of BC, which will be D.

parabola 2

Find the line at right angles to BC from D, and the intersection of this line and the vertical line, E, is a point on the parabola.

parabola 4

As point C is moved the parabola is traced out.

parabola 5

The picture is completed with the line BE. Check it!

 

 

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Filed under bisecting, conic sections, conics, construction, definitions, Uncategorized

Too Close for Comfort, a “must read” link

Forecasting the future of “education”, by Eli Horowitz

Prescient ??????

View story at Medium.com

View story at Medium.com

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Filed under education, future, horrors, humor, satire, school, transformations, Uncategorized

School——>PARCC tweet———>suspension———->and then?????

Thank you Audrey Watters for leading me to this exposure of the behaviour of testing corporations.

These two are MUST READs, and should be passed on to everybody:

http://www.bobbraunsledger.com/breaking-pearson-nj-spying-on-social-media-of-students-taking-parcc-tests/

http://kengreenwood.com/pearson_spying_on_kids/

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Filed under big brother, education, testing

“I can’t do math”

Not so long ago I was doing substitute (supply) teaching in a school in Yorkshire,England, and this happened:

“I can’t do math” she said to me.
“Oh yes you can and you will see
that you can do it on your own”.
I showed her how the cryptic code
was just a way of writing.
“The meaning’s there, give it a go,
and try to stop the fighting”.
The tunnel end came into view,
the light was bright and shining.
She did another, all alone,
and smiled with satisfaction.
Then turned to me and said again
“I can’t do math”

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Filed under humor, language in math, Uncategorized, verse