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40 votes
Find the slope-intercept equation of the line satisfying: Y-Int is 4 and goes through (1,8).

User Priyan Rajeevan
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1 Answer

12 votes
12 votes
Step-by-step explanation

Let's recall that the slope-intercept equation of a line has the form


y=mx+b,

where "m" is the slope, and "b" is the y-intercept. We know that the y-intercept is 4; then, our equation becomes


y=mx+4.

The trick to finding the slope is to note that the point (1,8) lies on the line; namely, we can evaluate the equation of the line in this point:


8=m\cdot1+4.

Solving this equation for m, we get


\begin{gathered} 8=m\cdot1+4, \\ 8=m+4, \\ 8-4=m+4-4, \\ 4=m, \\ m=4. \end{gathered}Answer

The equation of the line satisfying the provided conditions is


y=4x+4.

User Richard Nixon
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