Respuesta :

Answer:

a = 3

Step-by-step explanation:

The slope of a line given two points can be found by using the formula

[tex]m = \frac{ y_2 - y _ 1}{x_ 2 - x_ 1} \\ [/tex]

From the question the slope is - 3

To find the value of a we have

[tex] - 3 = \frac{7 - - 2}{a - 6} \\ - 3 = \frac{7 + 2}{a - 6} \\ - 3(a - 6) = 9 \\ - 3a + 18 = 9 \\ - 3a = 9 - 18 \\ - 3a = - 9[/tex]

Divide both sides by - 3

[tex] \frac{ - 3a}{ - 3} = \frac{ - 9}{ - 3} \\ [/tex]

We have the final answer as

a = 3

Hope this helps you

m =  y1 - y2 / x1 x2

-3 = -2 - 7 / 6 - a

-3 = -9 / 6 - a

-3 (6 - a)=-9

-18 + 3a = -9

3a = - 9 + 18

a = 9 / 3

a = 3