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What is the equation of the line in slope-intercept form?

What is the equation of the line in slope-intercept form?-example-1

1 Answer

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Answer:

2) y=-3x+36

Explanation:

Hi there!

We're given a graph and we want to find the equation of the line in slope-intercept form, which is y=mx+b, where m is the slope and b is the y intercept

We'll need two points, so pick any two from the graph

For example, let's do (0,36) and (12,0)

first let's find the slope

The formula for the slope calculated from two points is (y2-y1)/(x2-x1), where (x1,y1) and (x2,y2) are points

we'll be using (0,36) and (12,0)

let's label the points to avoid any confusion

x1=0

y1=36

x2=12

y2=0

Now substitute into the formula:

m=(y2-y1)/(x2-x1)

m=(0-36)/(12-0)

m=-36/12

m=-3

so the slope is -3

here's the equation so far:

y=-3x+b

we need to find b

The equation of the line will pass through both (0,36) and (12,0) so we can use either one of them to solve for b

let's take (12,0) for example

substitute 12 as x and 0 as y

0=-3(12)+b

multiply

0=-36+b

add 36 to both sides to isolate b

36=b

now substitute 36 as b into the equation

y=-3x+36

There's the equation of the line, so the answer is option 2

Hope this helps!

User Selvam
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