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What is an equation of the line that passes through the points (4, -6) and
(8,-4)?

User Steyn
by
3.5k points

1 Answer

5 votes

Answer:

y = 1/2x - 8

Explanation:

(4, -6) & (8, -4)

First you want to find the slope of the line that passes through these points. To find the slope of the line, we use the slope formula: (y₂ - y₁) / (x₂ - x₁)

Plug in these values:

(-4 - (-6)) / (8 - 4)

Simplify the parentheses.

= (2) / (4)

Simplify the fraction.

2/4

= 1/2

This is your slope. Plug this value into the standard slope-intercept equation of y = mx + b.

y = 1/2x + b

To find b, we want to plug in a value that we know is on this line: in this case, I will use the second point (8, -4). Plug in the x and y values into the x and y of the standard equation.

-4 = 1/2(8) + b

To find b, multiply the slope and the input of x(8)

-4 = 4 + b

Now, subtract 4 from both sides to isolate b.

-8 = b

Plug this into your standard equation.

y = 1/2x - 8

This is your equation.

Check this by plugging in the other point you have not checked yet (4, -6).

y = 1/2x - 8

-6 = 1/2(4) - 8

-6 = 2 - 8

-6 = -6

Your equation is correct.

Hope this helps!

User MusikPolice
by
2.7k points