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"Find x. (-7, -4), (x, 0); slope 1/3 How would you set up the equation to solve for x?"

A. y = 1/3x + 4
B. y = 1/3x - 4
C. y = 3x + 4
D. y = 3x - 4

User Sadhana
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1 Answer

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Final answer:

To find x, we use the slope-intercept form y = mx + b and the point (-7, -4) with the slope 1/3 to determine the y-intercept (-5/3). Then, we set up the equation y = (1/3)x - 5/3 and solve for x when y equals 0, resulting in x = 5.

Step-by-step explanation:

To find the value of x in the given slope problem, one would typically use the slope formula which is (y2 - y1) / (x2 - x1) = slope. However, since we are given a slope and one complete set of coordinates (-7, -4) along with a partially known set of coordinates (x, 0) wherein y is 0, we can use the slope-intercept form to set up the equation. The basic form of the slope-intercept equation is y = mx + b where m is the slope and b is the y-intercept.

First, let's find b, the y-intercept, using the known point (-7, -4) and the given slope 1/3:

-4 = (1/3)(-7) + b

-4 = -7/3 + b

b = -4 + 7/3

b = -12/3 + 7/3

b = -5/3

Now that we have the y-intercept, we can write the equation of the line as follows:

y = (1/3)x - 5/3

To find the value of x when y is 0, we set up the following equation:

0 = (1/3)x - 5/3

x = 5/3 × 3

x = 5

Hence, the value of x for which y would equal to 0 on this line is 5.

User XueYuan Wang
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