# What is the quadratic regression equation for the data set?

##### 1 Answer

#### Explanation:

#"substitute the given values for x into the equations and"#

#"check result against the corresponding value of y"#

#"the 'simplest ' value to start with is x = 10"#

#" starting with the first equation and working down"#

#"looking for an answer of "x=10toy=17.48#

#y=0.056x^2+1.278xto(color(red)(1))#

#color(white)(y)=(0.056xx100)+(1.278xx10)#

#color(white)(y)=5.6+12.78=18.38!=17.48#

#y=0.056x^2-1.278x-0.886to(color(red)(2))#

#color(white)(y)=(0.056xx100)-(1.278xx10)-0.886#

#color(white)(y)=5.6-12.78-0.886=-8.066!=17.48#

#y=0.056x^2+1.278to(color(red)(3))#

#color(white)(y)=(0.056xx100)+1.278#

#color(white)(y)=5.6+1.278=6.878!=17.48#

#y=0.056x^2+1.278x-0.886to(color(red)(4))#

#color(white)(y)=(0.056xx100)+(1.278xx10)-0.886#

#color(white)(y)=5.6+12.78-0.886=17.49~~17.48color(white)(x)✔︎#

#"this appears to be the correct equation"#

#"As a further test choose some other values of x "#