Draw the graph of $x + y = 7.$

Write four solutions for equations : $x=4 y$

Express the following linear equations in the form $ax + by + c = 0$ and indicate the values of $a$, $b$ and $c$ in each case : $2 x=-\,5 y$

For each of the graphs given in Fig. select the equation whose graph it is from the choices given below :

$(a)$ For Fig. $(i)$,

$(i)$ $x+y=0$           $(ii)$ $y=2 x$            $(iii)$ $y=x$             $(iv)$ $y=2 x+1$

$(b)$ For Fig. $(ii)$,

$(i)$ $x+y=0$           $(ii)$ $y=2 x$            $(iii)$ $y=2x+4$             $(iv)$ $y=x-4$

$(c)$ For Fig. $(iii)$,

$(i)$ $x+y=0$           $(ii)$ $y=2 x$            $(iii)$ $y=2x+1$             $(iv)$ $y=2 x-4$

Find the value of $k$, if $x = 2$, $y = 1$ is a solution of the equation $2x + 3y = k$.