82.3k views
1 vote
How do you write and equation of a linear function using two points

User Mgsloan
by
4.8k points

1 Answer

2 votes

Answer:

Explanation:

Find the difference between the 2 points.

For example, (8, 9) (5, 3).

Compare the difference between the x's, in this case 8 and 5. The difference is 3. Do the same with the y's, 9 and 3. The difference is 6.

To find the slope, it's y/x. The slope in this situation is 6/3. Simplify. The slope is 2.

To find the y-intercept, insert the slope and one of the 2 points in the beginning into y = mx + b & solve for b.

For example, if we use the ordered pair (5, 3) the equation would look like:

3 = 2(5) + b, Solve for b.

Multiply. 3 = 10 + b

Get b by itself by adding - 10 to both sides.

-7 = b

The y-intercept is -7. So, in this case, the equation is y = 2x - 7.

User Zhi Zhou
by
5.0k points