In 2005 Richard earned £22,000 per year. In 2015 Richard earned £31,900 per year.
Express this as a percentage increase.

for this case we have by definition, if two lines are perpendicular, then the product of their slopes is -1.

then, given the following line:

so,

we are looking for m_ {2}:

then, the line is given by:

we find "b" replacing the given point:

finally, the equation is:

option c