argh!!!! maths homework....very stuck and need some help!

[Jayzmummy]

Can some one explain transformations to me please?
DS1 has been set some homework today and it has to be handed in tomorrow or else he will be given extra homework for the weekend! The teacher handed it to them and said "lets see how you deal with this". DS1 hasnt a clue as he said they havent covered this subject at all before!!!!

He has a sheet and it asks some questions....

Translate shape A by translation vector (-6/1) and label image A1.
Reflect the A1 in the axis
Rotate A2 90 degrees anti-clockwise about the origin, label shape A3
Reflect A3 in the line y=-2
Reflect shape B in the line x =2
Reflect shape B in the X axis
Rotate shape B2 90 degrees anti-clockwise about point 4,2
Translate B3 translation vector (-5/2)

What the heck does all that mean?????
What is a translation vector?
Does anyone know any good maths homework sites for Year 7 pupils???
Please!

[jessicaandbumpsmummy]

YEAR 7?! WTF?! I have no idea sorry, but that seems a tad OTT for an 11 yr old

[katymac]

The vector co-ordinates are for the x and y axis (x,y) X is verticle and y is horitontal (I think)

Shape A is a square (for exaple) and has 4 corners represented by 4 sets of co-ordinates

Does that make sense so far?

[Jayzmummy]

Tell me about it....one minute they are reading Kipper and Chip....then they come home with axis and transformations.....I thought he was taking about a new rock band when he said "Hey Mum have you heard of transformations before"

Maths was never my strong point.....when will I ever use logarythms???....cant even spell it let alone remember it!!!!

[Lonelymum]

Right, I am not a Maths teacher, but if you don't get any better answers, let me start you off.

Get ds to write down the co-ordinates of shape A. Then, for each pair of co-ordinates, I think what he has to do is take 6 away from the first number and add one to the second.

Anyone agree with me so far?

This would give him new co-ordinates which he would then have to plot on his graph.

[Jayzmummy]

Katymac.....sounds like you know your stuff....go on....tell me more....please...Im on bended knee here
I dont want DS to think I am a real thicky!!

[NotQuiteCockney]

Translate shape A by translation vector just means, move shape a down 6 points and to the right 1.

Reflect the A1 in the axis means, um, don't know how to explain that, but you "flip" it over the midpoint.

Rotating you can do, right?

Draw a vertical line at -2, and reflect the shape over it.

x=2 is a horizontal line at +2.

X axis is the horizontal line at 0.

Rotating you can do again.

Translate is another move.

Am I making sense?

[katymac]

So have you written down the 4 co-ordinates?

Then take away 6 from the x co-ordinate and add 1 to the y (like Lonleymum said)

[katymac]

I'm assuming line 2 ends lable this A2
and has an x or y before the word axis?

[aloha]

Miss, my brain is full. Can I be excused?

If 11 year olds are supposed to do this, I take back everything I ever said about A level results.
I don't understand a single word of this thread.

(and if my ds was punished for not being able to do homework that wasn't explained, I would have a thing or two to say to the school. What IS the point of children's homework that is beyond the capability of intelligent adults with degrees?)

[katymac]

I'm trying to go slowly.....

[Lonelymum]

How is he getting on Jayzmummy?

[Lonelymum]

I'm with you katymac! Glad I was right about the first bit. Dh would be proud (and surprised) of me!

[Jayzmummy]

I think we are getting this.
He has a graph square that is divided into four...all are equal.
In the centre is the number 0.
Horizontal line has numbers -0 - -6 to the left of the zero and numbers 1-6 to the right of the zero.
Vertical line has numbers -1 --6 below the 0 and numbers 1-6 above.
In the upper right hand square there is a triangle. The points of which are at the positions 1 up 2 across. 1 up 4 across. 5 up 4 across.

Does that make sense???

[doddle]

Translate shape A by -6, 1, means move it along 6 squares left and up one and redraw it and label it A1.

Which axis do you have to reflect A1, if its the x axis its a reflection over the vertical line, if it the y you reflect it over the horizontal line, draw the new shape and call it A2.

Make this shape do a quarter turn clockwise about the point, (O,0), this is where the horizontal and vertical lines meet, draw the shape in the new position and call it A3.

Draw a horizontal line through the point y= -2 (that's 2 squares below the origin) reflect A3 over this line and call the new shape A4.



Shape B, draw a vertical line through x=2, that's 2 squares left of the origin, reflect shape B over it and call the new position B1.

reflect B1 over the line x=0, that's the vertical line that should be drawn for you) new shape becomes B2

find point 4,2 that's 4 right of 0,0 and 2 up, rotate B2 a quarter turn right draw the new shape and call it B3

move B3 5 squares lest and 2 up and that's your last shape.

A translation vector just tells you how many squares along and up to move something.

hth

[Lonelymum]

Yes. get him to take 6 away from the first number and add one to the second. Then plot that shape.

[doddle]

you all type faster than me!

[Jayzmummy]

so the new co-ordinates should be
-4 across and 2 up
-2 across and 2 up
-2 across and 6 up

is this right?

[Jayzmummy]

Im dyslexic and this is a nightmare!!!!!

[katymac]

1 up 2 across. (2,1)

1 up 4 across. (4,1)

5 up 4 across (4,5)

so to translate by (-6,1)

They would be

1 up 2 across. (2,1) (2-6,1+1) (-4,2)

1 up 4 across. (4,1) (4-6,1+1) (-2,2)

5 up 4 across (4,5) (4-6,5+1) (-2,6)


I hope

[doddle]

yep!!

[katymac]

Same as me....Great call this A1

Now is there an x or y in the second line?

[Jayzmummy]

Hold on.....we have added one up on the number so the image is 1 square higher than the original....is that wrong????

[katymac]

I think (without graph paper) it should be in the top left square (origonalin top right?)

[Jayzmummy]

we have put it in the top left square....but does the whole image have to move up one square?

[katymac]

Yes - I think so