Given:
A line passes through the points (9,9) and
.
The slope of the line is
.
To find:
The value of
.
Solution:
Slope formula:
![m=\dfrac{y_2-y_1}{x_2-x_1}](/tpl/images/1236/8028/d2381.png)
The line passes through the points (9,9) and
. So, the slope of the line is:
![m=\dfrac{-1-9}{x_2-9}](/tpl/images/1236/8028/f4a68.png)
![m=\dfrac{-10}{x_2-9}](/tpl/images/1236/8028/c7338.png)
It is given that the slope of the line is
.
![\dfrac{5}{6}=\dfrac{-10}{x_2-9}](/tpl/images/1236/8028/f3bc2.png)
![5(x_2-9)=-10(6)](/tpl/images/1236/8028/dedb2.png)
![5x_2-45=-60](/tpl/images/1236/8028/25797.png)
![5x_2=-60+45](/tpl/images/1236/8028/b1dbb.png)
![5x_2=-15](/tpl/images/1236/8028/7735a.png)
Divide both sides by 5.
![x_2=-\dfrac{15}{5}](/tpl/images/1236/8028/88e16.png)
![x_2=-3](/tpl/images/1236/8028/fd11b.png)
Therefore, the value of
is
.