Question

Y=6x Y=5x+7 Substitution method

Answer 1

$\left \{ {{y=6x} \atop {y=5x+7}} \right. \\\\Substitution\ method\\\\ 6x=5x+7\ \ \ | subtract\ 5x\\\\ x=7\\ y=6*7=42$

Answer 2

$\left\{\begin{array}{ccc}y=6x\\y=5x+7\end{array}\right\\\\subtitute\ y=6x\ to\ the\ second\ equation\\\\6x=5x+7\ \ \ \ \ |subtract\ 5x\ fron\ both\ sides\\\boxed{x=7}\\\\subtitute\ value\ of \x=7\ to\ the\ equation\ y=6x:\\\\y=6\cdot7\\\boxed{y=42}\\\\Answer:\\ \left\{\begin{array}{ccc}x=7\\y=42\end{array}\right$