Question

3.8x + y =-16- 3x + y =-5

Answer 1

let:

$\begin{gathered} 8x+y=-16_{\text{ }}(1) \\ -3x+y=-5_{\text{ }}(2) \end{gathered}$

Using elimination method:

$\begin{gathered} (1)-(2) \\ 8x-(-3x)+y-y=-16-(-5) \\ 11x=-11 \\ x=-\frac{11}{11} \\ x=-1 \end{gathered}$

Replace the value of x into (1):

$\begin{gathered} 8(-1)+y=-16 \\ -8+y=-16 \\ y=-16+8 \\ y=-8 \end{gathered}$