The equation of a line can be determined using the point slope formula:
y-y1=m (x-x1)
To make a substitution, we must ensure we have the correct information. The question gives:
y1=60
x1=50
y=1/2x+10 This is the formula of a line that is perpendicular to the one we are trying to find.
It tells us that the gradient of the perpendicular line is 1/2. The gradient of the line we are trying to find can be found using m1×m2=-1 because we know that when lines are perpendicular, the product of their gradients must equal 1
So if we replace m1 with 1/2
1/2×m2=-1
m2=-2
We now have all the relevant information to make a substitution:
