Question 83117
To find the equation of any linear graph you need 2 main things:
1. the gradient (slope) of the line.
2. any point on the line.
The general equation of any straight line is:
y=mx+b
where m is the gradient, and b is the y-intercept (the point at which the line crosses the y-axis).
To make the line perpendicular to g(x), the product of their gradients must be -1.
This means that the gradient of the line we are looking for is {{{-1/7}}}.
Next we can put in the point we have been given:
x=5, y=5
y=mx+b
{{{5=(-1/7)(5)+b}}}
{{{b=40/7}}}
{{{y=(-1/7) x+40/7}}}