Respuesta :

Answer:

k = 5.

Step-by-step explanation:

Equation of a line:

The equation of a line has the following format:

[tex]y = mx + b[/tex]

In which m is the slope, and b is the y-intercept(y when x = 0).

Perpendicular lines

When two lines are perpendicular, the multiplication of their slopes is -1.

Perpendicular to the line y=x−285.

This line has slope 1, so the line we want to find the equation has slope [tex]m = -1[/tex]

Then

[tex]y = -x + b[/tex]

Passes through (7, 0)

This means that when [tex]x = 7, y = 0[/tex]. So

[tex]y = -x + b[/tex]

[tex]0 = -7 + b[/tex]

[tex]b = 7[/tex]

So

[tex]y = -x + 7[/tex]

Find the value of k given that the line through (k, 2)

This means that when [tex]x = k, y = 2[/tex]. So

[tex]y = -x + 7[/tex]

[tex]2 = -k + 7[/tex]

[tex]k = 7 - 2 = 5[/tex]

The value of k is k = 5.