Respuesta :

A = (-7,-6)

B = (8,-9)

Find the slope of line AB

m = (y2-y1)/(x2-x1)

m = (-9-(-6))/(8-(-7))

m = (-9+6)/(8+7)

m = -3/15

m = -1/5

The slope of line AB is -1/5.

Flip the fraction and the sign to go from -1/5 to +5/1 = 5. The perpendicular slope is 5.

Let m = 5.

Use the coordinates of point C (2,12) along with the perpendicular slope to get

y - y1 = m(x - x1)

y - 12 = 5(x - 2)

y - 12 = 5x - 10

y = 5x - 10+12

y = 5x + 2

Lastly, convert this to standard form

y = 5x + 2

5x+2 = y

5x+2-y = 0

5x-y = -2

Choice A is the closest match, but the -56 should be -2 instead. It seems like your teacher made a typo somewhere.

oscar236

Answer:

5x - y = -2.

Step-by-step explanation:

The equation of this altitude line has a slope = -1/m where m is the slope of line AB . It will also pass through the point C.

The slope of line AB = (-9 - (-6)) / (8 - (-7))

= -3/15

= -1/5

So the slope  of the required line = -1 / -1/5 = 5.

Using the point C and the point-slope form of a line:

y - y1 = m(x - x1)

y - 12 =  5(x - 2)

y - 5x = -10 + 12

y - 5x = 2

5x - y = -2.

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