Question 154484
First, it's helpful to get your equations into the "slope-intercept" form.  Remember those? {{{y = mx+b}}} where m = the slope and b = the y-intercept.
{{{7x+2y = 9}}} Subtract 7x from both sides of the equation.
{{{7x-7x+2y = -7x+9}}} Simplify this.
{{{2y = -7x+9}}} Now divide both sides by 2 to get the y by itself.
{{{2y/2 = (-7x+9)/2}}} Simplify this.
{{{y = (-7/2)x+9/2}}} 
For the second equation:
{{{4x+5y = 6}}} Subtract 4x from both sides.
{{{5y = -4x+6}}} Divide both sides by 5.
{{{y = (-4/5)x + 6/5}}}
Since these are linear equations, their graphs will be straight lines and you need only two point to draw a straight line.  So, for each equation, first substitute x = 0 and solve for y, then substitute y = 0 then solve for x.
First equation:
The first point:
{{{y = (-7/2)x+9/2}}} Substitute x = 0 and solve for y.
{{{y = (-7/2)(0)+9/2}}}
{{{y = 9/2}}} This is one point: (0, 9/2)
The second point:
{{{y = (-4/5)x+6/5}}} Substitute y = 0 and solve for x.
{{{0 = (-4/5)x+6/5}}} Add {{{(4/5)x}}} to both sides.
{{{(4/5)x = 6/5}}} Multiply both sides by the multiplicative inverse of {{{4/5}}} and this is {{{5/4}}}
{{{x = 3/2}}} This is the other point: (3/2, 0) I'll leave the two points for other equation for you to find by using the same technique as above, starting with:
{{{y = (-4/5)x+6/5}}}
The graph will look like like:
{{{graph(400,400,-3,3,-3,6,(-7/2)x+9/2,(-4/5)x+6/5)}}}