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Write the slope-intercept form of an equation of the line that passes through the given point and is parallel to the graph of this equation: (- 1, - 4) , 9x + 3y = 8

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Answer

Equation of the line in slope-intercept form is

y = -3x - 7

Step-by-step explanation

Two lines that are parallel to each other have the same slopes.

So, we just need the slope of the line 9x + 3y = 8, and the point given for the line we need to write the equation of that line.

The slope and y-intercept form of the equation of a straight line is given as

y = mx + b

where

y = y-coordinate of a point on the line.

m = slope of the line.

x = x-coordinate of the point on the line whose y-coordinate is y.

b = y-intercept of the line.

To find the slope of the line, we need to put the equation given in the form of y = mx + b

9x + 3y = 8

3y = -9x + 8

Divide through by 3

(3y/3) = (-9x/3) + (8/3)

y = -3x + (8/3)

Comparing this with y = mx + b, we can see that

m = slope = -3

So for our line,

The general form of the equation in point-slope form is

y - y₁ = m (x - x₁)

where

y = y-coordinate of a point on the line.

y₁ = This refers to the y-coordinate of a given point on the line

m = slope of the line.

x = x-coordinate of the point on the line whose y-coordinate is y.

x₁ = x-coordinate of the given point on the line

m = slope = -3

Point = (x₁, y₁) = (-1, -4)

x₁ = -1

y₁ = -4

y - y₁ = m (x - x₁)

y - (-4) = -3 (x - (-1))

y + 4 = -3 (x + 1)

y + 4 = -3x - 3

y = -3x - 3 - 4

y = -3x - 7

Hope this Helps!!!