Question

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Answer 1

plug in 2 for y and 4 for x to find b

Answer 2

\[\text{Slope-Intercept Form} = y = mx + b\]\[y = \frac 12x + b\]\[2 = \frac 12(4) + b\]Solve for b.

Answer 3

Or you can use directly:

\[\large y - y_1 = m(x - x_1)\]

Here, \(m = \frac{1}{2} \; and \; (x_1,y_1) = (4,2)\)

Answer 4

How do you write it in slope intercept form?

Answer 5

I gave you the slope-intercept form.
y = mx + b
m = slope
Once you get b, put it in where b is here:
\(y = \frac12x + b\)