Question

A set of data points has an equation of = -1.5 + 2.5x.

What is the residual for the point (5,12)?

A. 11
B. -1
C. 1
D. 12

Answer 1

difference between the actual \(y\) value and the predicted \(y\) value
i.e. plug in \(5\) in to \(y=-1.5 + 2.5x\) for \(x\) and find what \(y\) you get

Answer 2

i get \(y=-1.5+2.5\times 5=11\)

Answer 3

i got 14

Answer 4

what did i do wrong?

Answer 5

but instead of \(11\) you have \(12\) which lies one unit above \(11\)

Answer 6

i don't know, i used a calculator

Answer 7

but we can do the arithmetic if you like

Answer 8

\[-1.5\times 2.5\times 5=-1.5+12.5=11\]

Answer 9

in any case since \(12\) is one unit higher, the "residual' is \(1\)

Answer 10

so i just plug in the y value in for x ?

Answer 11

oh you added!!

Answer 12

so the x value goes in the x spot right? and it supposed to equal the y value?

Answer 13

steps are
1) plug in \(5\) for \(x\) in the formula
2) compare the number you get with the \(y\) coordinate of \((5,12)\) i.e. compare it to \(12\)

Answer 14

got it ! thank you.

Answer 15

since \(12\) is one unit above the \(11\) you get from the formula, the "residual" is one

Answer 16

and for this one i would bet an even $10 that it is right
yw

Answer 17

you were right :)

Answer 18

does the y mean anything special? in the equation

Answer 19

on the link ^^

Answer 20

you know i don't actually know squat about data analysis, i just google "residual" to get your last answer
for this one, i would just replace \(x\) by \(15\) and see what you get
i can't imagine it can be anything else

Answer 21

alright thank you