Question

The graph shows the girth, in cm, of the trunk of a fir tree after different numbers of years:(Graph image may be below)

Answer 1

Answer:

Option A is correct.

the girth increases by 7 cm each year.

Step-by-step explanation:

Let y axis represents the girth in cm of the trunk of a fir tree and

x axis represents time in years.

Using the formula for slope : For any two points $(x_1 , y_1)$ and  $(x_2 , y_2)$ the slope of the line(m) is given by:

$m =\frac{y_2-y_1}{x_2-x_1}$

From the graph:

Take any two points to find the slope of the line:

Let two points be (0, 5) and (5, 40)

Then,  by the formula of slope:

$m =\frac{40-5}{5-0}=\frac{35}{5}$ = 7.

Therefore, The girth increases by 7 centimeters each year.

Answer 2

This is a linear function: y = mx + b, where m = slope and b, the value of y when x = 0

Having said that, the equation becomes : y = 7x+5

And the slope of the graph represents : A)The girth increases by 7 centimeters each year