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3. (3, 5) and (k, 9), slope = 1/2

Linear relationships unit 3 lesson 10 grade 8 openuprespurces

1 Answer

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Answer:

k = 11, if I understand the question.

Explanation:

Please rephrase the question if my interpretation is incorrect. (BTW, isn't (k,9) a dog?)

======================

I'll assume that we want to find the value of k as given by the equation of a line that has a slope of (1/2).

Let's determine if we can establish an equation with what we know:

1. It goes through point (3,5), and

2. It has a slope of (1/2)

We'll look for a line with the form y=mx+b, where m is the slope and b is the y-intercept (the value of y when x=0).

From (2) we know y = (1/2)x + b.

We can find b by using the one known point that lies on the line (3,5). Use y = (1/2)x + b, insert the point (3,5), and solve for b:

y = (1/2)x + b

5 = (1/2)(3) + b

5 = 1.5 + b

b = 3.5

The line is y = (1/2)x + 3.5.

Now use the point (k,9):

y = (1/2)x + 3.5

9 = (1/2)k + 3.5

(1/2)k = 5.5

k = 11

The point is (11,9) so k = 9

See the attached graph.

3. (3, 5) and (k, 9), slope = 1/2 Linear relationships unit 3 lesson 10 grade 8 openuprespurces-example-1
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