Your friend is trying to grow her hair as long as her cousin’s hair. the table shows their hair lengths y (in inches) in different months x. month friends hair(in) cousins hair(in) 3 4 7 8 6.5 9. solve for the cousins hair.

Given the table that shows the hair lengths y (in inches) of your friend and her cousin in different months x.

Month      Friends Hair(in)      Cousins Hair(in)
    3                     4                              7
    8                    6.5                            9.

To solve for the cousins hair, recall that the equation of a line is given by

y = mx + c

From the table,

7 = 3m + c . . . (1)
9 = 8m + c . . . (2)

(1) - (2) ⇒ -2 = -5m


Substituting for m into equation (1) gives:



Therefore, the equation representing the growth of the cousin's hair is given by y = 1.2x + 5.8