Solve the equations: 5x^2+4y^2=16 -----eqn 1 13x^2-5y^2=57-----eqn 2
anyone there
prolly try elimination, or a cramer rule
the y parts are prolly easiest to get rid of visually; multiply the top by 5 and the bottom by 4, than add em up
first i multiplied eqn 1 by 5 and 2 by 4 to get
and then added both equations
and the result is 77x=308
then the value of x will be coming+2,-2
that seems reasonable :) 5(5)x^2+4(5)y^2=16(5) 13(4)x^2-5(4)y^2=57(4) ------------------------ x^2(25+52) = 80+228 it looks like youve already solved it for the most part
then i substituted the value of x in eqn 1
i dont know the last part so that is why i am giving you all hints to solve last part of the question
are you allowed complex solutions?
5x^2 + 4y^2 = 16 the last part is to finish it up ....
on substituting in eqn 1 we will get the value of y i.e, what??????
if you did all that work by yourself above the rest should be a walk in the park for you 5(2)^2 + 4y^2 = 16 5(4) + 4y^2 = 16 20 + 4y^2 = 16 4y^2 = -4 y^2 = -1
first equation is an ellipse second is a hyperbola they do not intersect
since as amistre wrote you get \(y^2=-1\) which is certainly not possible with real numbers
it will be -1=i am i right
iota
if you are allowed numbers that fall outside of the set of "Real", then yes, it would be "i" otherwise there are no "Real" solutions
it is allowed
it will be +i and -i on squaring on both sides
its not done yet
now for x=-2 again the answer will be coming +i and -i
of course it is sine (+-2)^2 = 4
since
thank u all i was making a silly mistake
we all make the silly mistakes :)
thanks its done the solution set is {(2,+i,-i),(-2,+i,-i)} thanks the book shows the answer is absolutely right
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