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F (4) = 13 and f (0) = 21write an equation in point slope form

User Marco Borchert
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1 Answer

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9 votes

Answer

The equation of the line in point slope form is

y - 13 = -2 (x - 4)

Simplifying this further

y - 13 = -2x + 8

y = -2x + 8 + 13

y = -2x + 21

Step-by-step explanation

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

The coordinates of the points on the line are given in the form

f(x) = y

f(4) = 13 means (4, 13)

f(0) = 21 means (0, 21)

So, we need to calculate the slope of the line and use one of the points given as (x₁, y₁)

For a straight line, the slope of the line can be obtained when the coordinates of two points on the line are known. If the coordinates are (x₁, y₁) and (x₂, y₂), the slope is given as


Slope=m=\frac{Change\text{ in y}}{Change\text{ in x}}=(y_2-y_1)/(x_2-x_1)

(x₁, y₁) and (x₂, y₂) are (4, 13) and (0, 21)

x₁ = 4

y₁ = 13

x₂ = 0

y₂ = 21


\text{Slope = }(21-13)/(0-4)=(8)/(-4)=-2

m = -2

(x₁, y₁) = (4, 13)

x₁ = 4

y₁ = 13

y - y₁ = m (x - x₁)

y - 13 = -2 (x - 4)

Simplifying this further

y - 13 = -2x + 8

y = -2x + 8 + 13

y = -2x + 21

Hope this Helps!!!

User Helen Che
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3.3k points