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Write an equation of a line through (2,7.5) with an x-intercept of -1

User Noki
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1 Answer

2 votes

Answer:

y = (5/2)x + 5/2

Explanation:

The coordinates of the given x-intercept are (-1, 0).

As we move to the right from (-1, 0) to (2. 7.5), x increases by 3 and y by 7.5.

Thus, the slope of this line is m = rise / run = 7.5 / 3, or 75 / 30, or 5/2.

Thus, starting from y = mx + b, we have:

7.5 = (5/2)(2) + b, or

7.5 = 5 + b

Thus, b = 2.5, and the equation is

y = (5/2)x + 5/2

check: Is 7.5 = (5/2)(2) + 5/2 true?

Is 7.5 = 5 + 5/2 true? YES

User PawelPredki
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