Maths, Addmaths and Statistics: Post your doubts here!

[Altamash Haroon]

How to do this question?

Find the coordinates of the point where the line 2y = 3x + 15 crosses the y-axis.

 

[farhan141]

How to do this question?

Find the coordinates of the point where the line 2y = 3x + 15 crosses the y-axis.

When Line passes through Y-Axis then x=0

So, 2y=3(0)+15

2y=15

Y=7.5.

Therefore, co-ordinates = (0,7.5)

 

[danial 234]

PLEASE SOMEONE HELP ME IN CENTER OF ROTATION. PLEASE.

suppose the image of ABC by rotation is A'B'C' then join all the corresponding points as A to A' ,B to B'.
then find the bisector of each line. the point where the bisectors intersect is centre of rotation.

 

[danial 234]

thankuuuu so much can u help me with this one too
meiling can complete a piece of work in 12 days and suling can complete it in 18 days .findthe number of days in which both,working together will take to complete the work

for this type of questions the method is same
1/12+1/18=1/x
x= no of days together

 

[TheStallion-Reborn]

are the opposite angle in EVERY quadrilateral supplementary? and is there a set of notes available which addresses the 'RATTA' topics lyk angle properties, lines of symmetry order of rotation symmetry etc?

 

[danial 234]

Can somebody help solving this! the last two parts!View attachment 27569

a)AR= AB+BR
=p+k(q/2)
post the answers of 1st two so i can answer the last part as i m too exhausted to attempt the other parts as well

 

[danial 234]

are the opposite angle in EVERY quadrilateral supplementary? and is there a set of notes available which addresses the 'RATTA' topics lyk angle properties, lines of symmetry order of rotation symmetry etc?

not in trapezium

 

[Altamash Haroon]

When Line passes through Y-Axis then x=0

So, 2y=3(0)+15

2y=15

Y=7.5.

Therefore, co-ordinates = (0,7.5)

thanks, but how do you know that when line passes through Y-axis, then x=0??

 

[TheStallion-Reborn]

thanks, but how do you know that when line passes through Y-axis, then x=0??

on any grid, draq a random line, pass it thru y axis and check the value of x

 

[TheStallion-Reborn]

not in trapezium

what if a trapezium is made inside a circle??(cyclic quadrilateral)

 

[farhan141]

thanks, but how do you know that when line passes through Y-axis, then x=0??

It's a general rule bro.

If line passes through y-axis then Value of x = 0

If line passes through x-axis then Value of y = 0

Hope you got it.

 

[farhan141]

suppose the image of ABC by rotation is A'B'C' then join all the corresponding points as A to A' ,B to B'.
then find the bisector of each line. the point where the bisectors intersect is centre of rotation.

Can u draw somewhere or link me to another site where they explain it in detail?

 

[Sikander Khan]

a)AR= AB+BR
=p+k(q/2)
post the answers of 1st two so i can answer the last part as i m too exhausted to attempt the other parts as well

2ND LAST ONE IS P+K/2 Q
AND LAST ONE K= 5

 

[danial 234]

symmetry ORDER OF ROTATIONAL SYMMETRY
SQUARE 4 4
RECTANGLE 2 2
EQUILATERAL TRIANGLE 3 3
PARALLELOGRAM 0 2
ISOSCELES TRIANGLE 1 1
CIRCLE INFINITE
RHOMBUS 2 2
TRAPEZIUM 0
TRAPEZIUM WITH TWO EQUAL SIDES 1 1
KITE 1
IF THE DIAGRAM IS 3D AS THE SQUARE BECOMES A CUBE ADD 1 TO THE SYMMETRY

 

[danial 234]

T

what if a trapezium is made inside a circle??(cyclic quadrilateral)

THEN IT WILL BE CORRECT BUT NOT OUTSIDE

 

[danial 234]

FARHAN
I HOPE THAT IT MIGHT HELP
http://www.google.com.pk/url?sa=t&r...j4HICA&usg=AFQjCNHHHuzMCpCkjr4-xTHzOGLu5Z7TBw

 

[farhan141]

Thanks. Turn off your caps lock. It's annoying.

 

[danial 234]

Thanks. Turn off your caps lock. It's annoying.

by the way what issue do you have with my caps lock

 

[areela hassan]

thanks dude u r awsum!!

for this type of questions the method is same
1/12+1/18=1/x
x= no of days together

 

[usama321]

FARHAN
I HOPE THAT IT MIGHT HELP
http://www.google.com.pk/url?sa=t&rct=j&q=how to find centre of rotation&source=web&cd=8&cad=rja&ved=0CGoQFjAH&url=http://www.absorblearning.com/media/item.action?quick=ha&ei=1OChUcS0LMiohAfej4HICA&usg=AFQjCNHHHuzMCpCkjr4-xTHzOGLu5Z7TBw

an easier way would be to just make pairs of arcs from corresponding vertices of the triangle, and make the perpendicular bisectors that way. There is lesser chance of error, and less time wasted