The length L (in centimeters) of a copper rod is a linear function of its Celsius temperature C. In an experiment, if L = 124.942, when C = 20 and L = 125.134, when = 110, express L is term of C.

Given: L - aC + b

Now L = 124.942 and C = 20

Therefore, 20a + b = 124.942 ….(1)

Again when L = 125.134 and C = 110

110a + b = 125.134

From (i) and (ii) on substraction

90a = 0.192

or a =

⇒ 20 × = 124.942

or b = 124.942 -

Thus, L = +124.942 -

Hence, L =