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Find the equation of a line that contains the points (2,1) and (8,7). Write the equation in slope-intercept form.

User JCotton
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3.8k points

1 Answer

6 votes

Answer:

y = x - 1

Explanation:

First find the slope. Subtract the y's and put that on top of a fraction. Then subtract x's and put that on the bottom. Simplify if possible.

7-1 is 6 goes on top.

8-2 is 6 goes below.

6/6 is 1 when simplified.

Slope is 1.

Slope-intercept form is y = mx + b.

m is slope, so fill that in.

y = (1)x + b

Now we need to find b.

Use either one of the given points; they will give you the same answer no matter which one you choose. Let's use (2,1) because smaller numbers.

y is 1 and x is 2.

y= (1)x + b

1 = (1)2 + b

1 = 2 + b

-1 = b

Now fill in both m and b. Leave x and y as letters (variables)

y = (1)x + -1

Final answer:

y = x - 1

User Pear
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3.6k points