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2 votes
Write an equation
of the line in slope - Intercept form
(8,3) (0,-5)

User Miles Fett
by
4.9k points

1 Answer

4 votes

Answer:

y=x-5

Explanation:

Hi there!

We want to write an equation of the line that passes through the points (8,3) and (0,-5) in slope-intercept form

Slope-intercept form is given as y=mx+b, where m is the slope, and b is the y intercept

So let's first find the slope of the line

The formula for the slope calculated from two points is
(y_2-y_1)/(x_2-x_1), where
(x_1, y_1) and
(x_2, y_2) are points

We have everything needed to find the slope, but let's label the values of the points to avoid any confusion


x_1=8\\y_1=3\\x_2=0\\y_2=-5

Now substitute into the formula

m=
(y_2-y_1)/(x_2-x_1)

m=
(-5-3)/(0-8)

Subtract

m=
(-8)/(-8)

Simplify

m=1

The slope is 1

Here is the equation of the line so far:

y=1x+b (can also be written as y=x+b)

We need to find b

The equation passes through both (8, 3) and (0, -5), so we can substitute the values of either one of them as x and y to solve for b

Let's take (8, 3) for example

Substitute 8 as x and 3 as y

3=1(8)+b

Multiply

3=8+b

Subtract 8 from both sides

-5=b

Substitute -5 as b into the equation

y=x-5

Hope this helps!

User Jive Boogie
by
5.2k points