Question

Determine which method works, substitution or elimination? 4x^2+3y^2=42x^2-6y^2=-3

Answer 1

Given:

`\begin{gathered} 4x^2+3y^2=4 \\ \\ 2x^2-6y^2=-3 \end{gathered}`

Find the method .

Sol:

`\begin{gathered} 4x^2+3y^2=4..............(1) \\ \\ 2x^2-6y^2=-3.............(2) \end{gathered}`

2eq(1) + eq(2) then,

`8x^2+6y^2=8`

Then apply the elimination method.

`\begin{gathered} 8x^2+6y^2=8 \\ 2x^2-6y^2=-3 \\ --------- \\ 10x^2=5 \\ \\ x^2=(5)/(10) \\ \\ x=\sqrt{(1)/(2)} \end{gathered}`