The lines below are perpendicular. If the slope of the solid line is 4, what is the slope of the dashed line?

The equation above shows how temperature f, measured in degrees fahrenheit, relates to a temperature c, measured in degrees celsius. based on the equation, which of the following must be true? a temperature increase of 1 degree fahrenheit is equivalent to a temperature increase of 5/9 degree celsius. a temperature increase of 1 degree celsius is equivalent to a temperature increase of 1.8 degrees fahrenheit. a temperature increase of 5/9 degree fahrenheit is equivalent to a temperature increase of 1 degree celsius. a) i only b) ii only c) iii only d) i and ii only