Question

The table shows the lengths (in inches) of your hair months after your last haircut. The points in the table lie on a line. Find and interpret the slope of the line. After how many months is your hair $4inches$ long?

Answer 1

In mathematics, the slope or gradient of a line is a number that describes both the direction and the steepness of the line.

Slope is often denoted by the letter $m$

Determine the slope of the line using two points from the table:
$(2,1)\mathrm{and}(4,2)$

$(x_1,y_1)=(2,1)$
$(x_2,y_2)=(4,2)$

$m=\frac{y_2-y_1}{x_2-x_1}=\frac{2-1}{4-2}=\frac{1}{2}=0.5$

This means that each month the hair grows $0.5inches$
As the hair grows $0.5inches/month$, it will be $4inches$ long after $\frac{4}{0.5}$$=8months$

Hence after $8months$hairs will be $4inches$ long.