# Write an equation for the line

It is important to note that the equation of a line in three dimensions is not unique. Choosing a different point and a multiple of the vector will yield a different equation. This is representation of the line is equivalent to the one found above. Why is this fascinating? Because if we are ever asked to solve problems involving the slope of a tangent line, all we need are the same skills we learned back in Algebra for writing equations of lines.

In fact, we are going to see that there are only a few simple steps for writing the equation of a tangent line or normal line perpendicular line to a curve at a given point. As wikiHownicely explains, to find the equation of a line tangent to a curve at a certain point, you have to find the slope of the curve at that point, which requires calculus.

Meaning, we need to find the first derivative.

 Was this information helpful? You actually need some way of anchoring this line to a fixed point on the graph. Based on that introduction, you may already have figured out what you need for your line equation. Tutorial on Equation of Line Standard Form of a Line by: Discussion The standard form of a line is just another way of writing the equation of a line. Standard Form of a Line We can move the x term to the left side by adding 2x to both sides. We have seen that we can transform slope-intercept form equations into standard form equations.

Here are the steps: Substitute the given x-value into the function to find the y-value or point. Calculate the first derivative of f x Plug the ordered pair into the derivative to find the slope at that point Substitute both the point and the slope from steps 1 and 3 into Point-Slope Form to find the equation for the line tangent line Example of How to Write the Equation of the Line Tangent to a Curve Remember, all we need to write an equation of a line is a point and a slope!

Together we will walk through three examples and learn how to use the point-slope form to write the equation of tangent lines and normal lines. This will lead us nicely into our next lesson which is all about how Linear Approximation. In other words, the tangent line is the graph of a locally linear approximation of the function near the point of tangency.

This means we can approximate values close to the given point by using the tangent line. This process is called Linearization of a function. The following practice problems contain three examples of how to use the equation of a tangent line to approximate a value.Let's find the equation of the line that passes through the points.

This one's a two-stepper STEP 1: Find the slope. continue. 1 2. Lines. What's the Slope of a Line? Finding the Slope of a Line from the Graph.

Finding the Slope of a Line from Two Points. Linear Equations. Question: Write an equation in slope intercept form for the line that passes through the points (5,-1) and (2,-7) Equation of a Line: There are a few different forms for the equation of a line. Hi Alex, Think about the graph of the vertical line through (6, -2). The x-coordinate of every point on the graph is 6. Furthermore if a point in the plane is not on the graph then its x-coordinate is not 6. To answer this we will first need to write down the equation of the line.

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We know a point on the line and just need a parallel vector. We know that the new line must be parallel to the line given by the parametric equations in the problem statement. write the equation of the line through (1,0) and (2,-2) Math Problem Word Problem Algebra 1 Slope Equation Word Problems Algebra College Algebra Linear Equations And Inequalities Solving Linear Equations Calculus.

Receive answers to your questions from . Oct 09,  · No registration required to write. Equation of a Line, Slope. Post a new topic. 4 topics • Page 1 of 1. Topics Equation of a line through 2 points by Guest» Mon Oct 10, am 8 Replies Views Last post by Guest Tue Feb 02, pm; A quick fraction question about line slope by mklangelo» Fri Oct 07, am 3.

General Equation of a Line: ax + by = c