Bryce wrote the linear regression equation y = 1.123 x minus 6.443 to predict the armspan, y, of a person who is x inches tall. Riley has an armspan of 67.5 inches. Which is the best prediction of Riley's height?

equation is y = 1.123x - 6.443 where y represents the armspan and x represents the height. Now we need to find the height, when armspan = 67.5 inches. SO we need to plug 67.5 for y and solve for x that is

67.5 = 1.123x - 6.443

adding 6.443 to both sides

67.5 + 6.443 = 1.123x

73.943 = 1.123x

Dividing both sides by 1.123

x = 65.84 inches.

So for the given armspan of 67.5 inches, height is 65.84 inches.