We know that, in a linear function, the rate of change is constant for any two points on the line.
Table 1
Given,
![](https://lh6.googleusercontent.com/yeyetXiq1vpTnE_kRDJepIOw6PHhlE_qACCsNMHzB97NBCt8Pl7aAxg_DoIf2zm4pexRNPQHJQ8yj_KJ_ILDu8pgaLDZoGfsYXiygUJrTgZeNot4mRCzJCpMUFcOkkaUl381rkZB)
Let’s consider a set of two points
(8,8) and (10,10).
Slope
=Change in yChange in x=(10−8)(10−8)=22=1
Consider another set of two points
(10,10) and (13,13).
Slope
=Change in yChange in x=(13−10)(13−10)=33=1
Consider another set of two points
(13,13) and (16,16).
Slope
=Change in yChange in x=(16−13)(16−13)=33=1
Since the slope is constant, the function represented by the given table is linear.
Table 2
Given:
![](https://lh3.googleusercontent.com/QrJ9lY17KUUdKKI2vYN4TodNQVyhZUI8m6c6d4KyYwYojgqPNr1KLTY1Fdi-EM-oigWT3sLsvKkaAphesA3-XQ0aLhhED45V-tm04l9KWUFnmRml0nTY__6M2quwe3NsrJ2yRo-2)
Let’s consider a set of two points
(17,20) and (18,14).
Slope
=CChange in yCChange in x=(14−20)(18−17)=−61=−6
Consider another set of two points
(18,14) and (19,7).
Slope
=Change in yChange in x=(7−14)(19−18)=−71=−7
Consider another set of two points
(19,7) and (20,2).
Slope
=Change in yChange in x=(2−7)(20−19)=−51=−5
Since the slope is constant, the function represented by the given table is linear.
Option A is correct.