Question 118·Easy·Linear Equations in Two Variables
A line passes through the points and in the -plane. What is the slope of the line?
(Express the answer as an integer)
When a question asks for the slope of a line through two points, immediately write the slope formula . Carefully label the coordinates, choose an order for the points, and stick to that order in both the numerator and denominator to avoid sign mistakes. Do the two subtractions, then divide and simplify; keeping the process mechanical and consistent helps you work quickly and avoid common errors like flipping the fraction.
Hints
Think about what slope measures
Slope measures how much changes when increases by 1 unit. It is change in divided by change in .
Use the two points to find changes
Find how much the -value changes going from to , and how much the -value changes over the same move.
Form the ratio correctly
Once you know the change in and the change in , put change in in the numerator and change in in the denominator, then simplify the fraction.
Desmos Guide
Use Desmos to compute the slope expression
In a Desmos expression line, type (15 - 7) / (6 - 2) and press Enter. The numerical value that Desmos displays is the slope of the line through and .
Step-by-step Explanation
Recall the slope formula
The slope of a line that passes through two points and is given by
That is, slope equals change in divided by change in .
Label the points and substitute
Label the points as follows:
- First point (2,7)$
- Second point (6,15)$
Substitute these into the slope formula:
Compute the differences and simplify
Now calculate the numerator and denominator:
So the slope is
Therefore, the slope of the line is .