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Write an equation of the line that passes through a pair of points: 5 4 37 2 1+ 4 -3 -2 -1 1 -3 a. y = x + 3 b. y = x - 3 C. y = -x + 2 d. y = -x-2 Please select the best answer from the choicon

User Dave Causey
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1 Answer

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From the given, it shows two points that pass through the given graph. These points are:

Point A : x1, y1 = 4, 1

Point B : x2, y2 = 5, 2

We will be using these points in generating the equation of the line.

Step 1: Let's determine the slope m of the line.


\text{ m = }(y_2-y_1)/(x_2-x_1)\text{ = }\frac{\text{ 2 - 1}}{\text{ 5 - 4}}\text{ = }(1)/(1)\text{ = 1}

Step 2: Let's determine the y-intercept b. Substitute x,y = 4, 1 and m = 1 in y = mx + b.


\text{ y = mx + b}
\text{ 1 = (1)(4) + b}
\text{ 1 = 4 + b}
\text{ 1 - 4 = b}
\text{ -3 = b}

Step 3: Let's complete the equation. Substitute m = 1 and b = -3 in y = mx + b.


\text{ y = mx + b}
\text{ y = (1)x + (-3)}
\text{ y = x - 3}

Therefore, the equation of the line is y = x - 3.

The answer is letter B.

User Jim Horng
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2.9k points