Welcome to Westonci.ca, the place where your questions are answered by a community of knowledgeable contributors. Experience the ease of finding precise answers to your questions from a knowledgeable community of experts. Join our platform to connect with experts ready to provide precise answers to your questions in different areas.

solve the following system of linear equations by substitution:
8x-y=-13
6x-3y=15


Sagot :

Rearrange 8x-y=-13 to y=8x+13
Substitute this in so:
6x-3(8x+13)=15
6x-24x-39=15
-18x-39=15
-18x=54
x=-3

Substitute x into 1st equation:
Y=(8*-3)+13
Y=-24+13
Y=-11
Lilith
[tex]\begin{cases} 8x-y=-13 \\ 6x-3y=15 \end{cases}\\ \\ \begin{cases} -y=-8x-13 \ \ *(-1) \\ 6x-3y=15 \end{cases}\\ \\\begin{cases} y= 8x+13 \\ 6x-3(8x+13)=15 \end{cases} \\ \\\begin{cases} y= 8x+13 \\ 6x-24x-39=15 \end{cases}[/tex]

[tex]\begin{cases} y= 8x+13 \\ 6x-24x =15+39 \end{cases} \\ \\\begin{cases} y= 8x+13 \\ -18x =54 \ \ / :(-18)\end{cases} \\ \\\begin{cases} y= 8*(-3)+13 \\ x = -3 \end{cases} \\ \\\begin{cases} y= -24+13 \\ x = -3 \end{cases} \\ \\ \begin{cases} y= -11 \\ x = -3 \end{cases}[/tex]