Answer:
x + 3y = 30
Step-by-step explanation:
We are given that a line contains the points (12,6) and (-3,11).
We want to write the equation of this line in standard form.
Standard form is written as ax+by=c, where a, b, and c are free integer coefficients, however a and b cannot be 0, and a cannot be negative.
Regardless, before we write an equation in slope-intercept form, we must first write the equation in a different form, such as slope-intercept form.
Slope-intercept form is given as y=mx+b, where m is the slope and b is the value of y at the y-intercept.
So first, let's find the slope of the line.
The slope (m) can be found using the formula
, where
and
are points.
Even though we already have 2 points, let's label their values to avoid any confusion and mistakes when calculating.
![x_1=12\\y_1=6\\x_2=-3\\y_2=11](https://tex.z-dn.net/?f=x_1%3D12%5C%5Cy_1%3D6%5C%5Cx_2%3D-3%5C%5Cy_2%3D11)
Now substitute these values into the formula.
m=![\frac{y_2-y_1}{x_2-x_1}](https://tex.z-dn.net/?f=%5Cfrac%7By_2-y_1%7D%7Bx_2-x_1%7D)
m=![\frac{11-6}{-3-12}](https://tex.z-dn.net/?f=%5Cfrac%7B11-6%7D%7B-3-12%7D)
Subtract
m=![\frac{5}{-15}](https://tex.z-dn.net/?f=%5Cfrac%7B5%7D%7B-15%7D)
Simplify
m=![-\frac{1}{3}](https://tex.z-dn.net/?f=-%5Cfrac%7B1%7D%7B3%7D)
The slope is -1/3
Here is the equation of the line so far in slope-intercept form:
![y=-\frac{1}{3} x + b](https://tex.z-dn.net/?f=y%3D-%5Cfrac%7B1%7D%7B3%7D%20x%20%2B%20b)
We need to solve for b.
As the equation passes through (12,6) and (-3,11), we can use either one to help solve for b.
Taking (12, 6) for example:
![6=-\frac{1}{3}(12) + b](https://tex.z-dn.net/?f=6%3D-%5Cfrac%7B1%7D%7B3%7D%2812%29%20%20%2B%20b)
Multiply
![6=-\frac{12}{3} + b](https://tex.z-dn.net/?f=6%3D-%5Cfrac%7B12%7D%7B3%7D%20%20%2B%20b)
Divide
6 = -4 + b
Add 4 to both sides.
10 = b
Substitute 10 as b in the equation.
![y = -\frac{1}{3} x + 10](https://tex.z-dn.net/?f=y%20%3D%20-%5Cfrac%7B1%7D%7B3%7D%20x%20%2B%2010)
Here is the equation in slope-intercept form, but remember, we want it in standard form.
In standard form, the values of both x and y are on the same side, so let's add -1/3x to both sides.
![\frac{1}{3} x + y = 10](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B3%7D%20x%20%2B%20y%20%3D%2010)
Remember that a (the coefficient in front of x) has to be an integer, 1/3 is not an integer.
So, let's multiply both sides by 3 to clear the fraction.
![3(\frac{1}{3} x + y) = 3(10)](https://tex.z-dn.net/?f=3%28%5Cfrac%7B1%7D%7B3%7D%20x%20%2B%20y%29%20%3D%203%2810%29)
Multiply.
<u>x + 3y = 30</u>
<u></u>
Topic: finding the equation of the line (standard form)
See more: brainly.com/question/27575555