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Write the slope-intercept form of the equation of the line.

slope = -10, y-intercept = 5

Write the slope-intercept form of the equation of the line.
through: (-5,-1), slope = 2/5

Write the slope-intercept form of the equation of the line.
through: (5,0) and (-5,2)

Write the slope-intercept form of the equation of the line.
through: (-5,0), parallel to y = -x + 2

1
Write the slope-intercept form of the equation of the line.
through: (4,1), perpendicular to y = -2x + 5

1 Answer

12 votes

Answer:

y = -10x + 5 and y = 2/5x + 1

Explanation:

slope-intercept form is y = mx + b, where m = slope and b = y-intercept.

for your first problem, just plug in the m and b values to complete the equation.

1.) y = mx + b ⇒ y = -10x + 5

plug in -10 for x (slope) and 5 for b (y-intercept)

and for the second problem...

since you're given a value for slope as well as a coordinate pair, all you need to do is plug those values into the equation for their respective variables and then solve for b. (it doesn't matter what order you plug values in, but i'm going to fill them in in the order of the equation; y, m, and x)

1.) plug in -1 for y

y = mx + b ⇒ -1 = mx + b

2.) plug in 2/5 for m

-1 = mx + b ⇒ -1 = 2/5x + b

3.) plug in -5 for x

-1 = 2/5x + b ⇒ -1 = 2/5(-5) + b

now it's time to solve for b! start by multiplying 2/5 and -5.

-1 = 2/5(-5) + b ⇒ -1 = -2 + b

add 2 to both sides of the equation. on the right side, it cancels itself out. on the left side, adding 2 to -1 gives you 1.

and you're left with 1 = b! :)

therefore, y = 2/5x + 1

i hope this helps! have a great day <3

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