elimination method

[moosie2323]

How would I set this problem up to solve by the elimination method
4x^2-9y^2+132=0
x^2+4y^2-67=0

 

[Aladdin]

How would I set this problem up to solve by the elimination method
4x^2-9y^2+132=0
x^2+4y^2-67=0

$\displaystyle 4x^2 - 9y^2 = -132$
$\displaystyle x^2 + 4y^2 = 67$

mMm, Let us eliminate x . So I'll multiply the second equation with ( -4 ).

$\displaystyle 4x^2 - 9y^2 = -132$
$\displaystyle -4x^2 - 16y^2 = -268$
.
.
$\displaystyle -25y^2 = -400$
$\displaystyle y^2 =\frac{400}{25}$

$\displaystyle y^2 = 16$
$\displaystyle y = -+ 4$

Now substitute y^2= 16 in the second equation to find x, knowing that x also have two values.

 

[Deleted member 4993]

$\displaystyle y = -+ 4$

Now substitute y^2= 16 in the second equation to find x, knowing that x also have two values.

in LaTex you can use "\pm" to get ±.

like

$\displaystyle \pm 4$

 

[Aladdin]

$\displaystyle y = -+ 4$

Now substitute y^2= 16 in the second equation to find x, knowing that x also have two values.

in LaTex you can use "\pm" to get ±.

like

$\displaystyle \pm 4$

Thank you Mr khan.