- #1

chwala

Gold Member

- 2,708

- 375

- Homework Statement
- See attached

- Relevant Equations
- understanding of vectors and simultaneous equation

Find the question and solution here;

Ok, i was able to solve this by using,

##3A=3ax+12ay+6bx+3by+3b##

##2B=2ay-4ax+4a+4bx-6by-2b##

leading us to the simultaneous equation;

##7x+10y=4##

##2x+9b=-5##

##x=2## and ##y=-1##

I had initially tried the approach of using ##3A=2B## →##B=1.5A## ...Then on substituting this in ##A##, I got

##B_1= 1.5a(x+4y) + 1.5b(2x+y+1)## this ought to be equal to,

##B_2 = a(y-2x+2)+b(2x-3y-1)##

giving me the simultaneous equation,

##3.5x+5y=2##

##x+4.5b=-2.5##

aaaaargh this is also correct, i had missed out on a term...

any other approach guys welcome...

##3A=3ax+12ay+6bx+3by+3b##

##2B=2ay-4ax+4a+4bx-6by-2b##

leading us to the simultaneous equation;

##7x+10y=4##

##2x+9b=-5##

##x=2## and ##y=-1##

I had initially tried the approach of using ##3A=2B## →##B=1.5A## ...Then on substituting this in ##A##, I got

##B_1= 1.5a(x+4y) + 1.5b(2x+y+1)## this ought to be equal to,

##B_2 = a(y-2x+2)+b(2x-3y-1)##

giving me the simultaneous equation,

##3.5x+5y=2##

##x+4.5b=-2.5##

aaaaargh this is also correct, i had missed out on a term...

any other approach guys welcome...

Last edited: