10 points for this answer...?

Question

Find the values of x and y that satisfy the equation
(x + y) +j(x - y) = 4.4 - j1.2
(show working out)

Answer 1

well... the real and imaginary parts of this equation must be equal, so we can split it into two simultaneous equations:

x+y=4.4 and
x-y=-1.2
simply adding the two together gives us:
x+y+x-y=4.4-1.2
2x=3.2
x=1.6
and substituting x into one of our equations:
x+y=4.4
1.6+y=4.4
y=2.8

and, of course, its always worth checking that these figures work:
(x + y) +j(x - y)
1.6 + 2.8 + j(1.6-2.8)
=4.4+j(-1.2)
=4.4-j1.2

And we're done.

Answer 2

I can think of no possible value to the equation! I can think of many values to not doing the equation, like going for a stroll with the dog, munching my way through a huge bar of chocolate. Even persuading you to give me 10 points for imagination.

Answer 3

I made it that x = 1.6
y = -0.933
j = 7.00

It took me ages and I think it is wrong, but you didn't ask for a correct answer. Here is the method, though:

First find x by dividing both sides by j to get rid of it.

Then when you have a value for x, put it back in to the equation as a number, and get rid of the y by dividing both sides by y, so that you get a value for j

Put the numerical values back in for j & x, giving you just one unknown (y) and work it to get a value for j.

That is what I did to get the values I gave at the top, but they seem wrong because when you put the values for x,y, & j back in, it does not equal.

Sorry! I really did try.

:-)

Answer 4

That's a simple algebraic problem.
the real part of the right side of the equation must be equal to the real part of the left side
thus

x+y = 4.4

and
the imaginary part of the right side of the equation must be equal to the real part of the imaginary side
thus

x-y=-1.2

solving them simultneously.
x+y=4.4
x-y=-1.2

adding them will make it
2x = 3.2
x = 1.6

and subtracting them will make it
2y=5.6
y=2.8

therefore
x=1.6 and y=2.8


I'm expecting for the 10 points
thanks

Answer 5

I used to love quadratic equations ar school, but have not used them for 20 years and wouldn't know where to start!!!

Answer 6

Surely you need to know the values of X or y?

Are you cheating by any chance? HA HA

Answer 7

You have a pair of linear equations:
x+y = 4.4
x-y = -1.2

Add both equations together and simplify:
2x = 3.2

Hence, divide by 2 gives:
x = 1.6

Substitute in either equation above to give
y = 2.8

Answer 8

Another delightfully asked question. "Love" the demand for workings out as well.

Do it yourself.

Answer 9

separate real and imaginary

x+y=4.4............(1)
jx-jy= -j1.2
x-y= -1.2...........(2)

add (1) and (2)
2x=3.2>>>>>x=1.6
substitute into (1)
1.6+y=4.4>>>>>y=2.8

i hope that this helps

Answer 10

This can be done by equating coefficients.