Answer:
x=
Step-by-step explanation:
3x-12-6x+21=23
-3x+9=23
-3x=14
x=
Answer:

Step-by-step explanation:
stupid enough
y=mx+b

slope = 16-12/3-6
-4/3

plug in x and y
16=-4/3(3)+b
b=20
<h2><em><u>Red</u></em></h2>
To find the slope of a line that goes through given points with known coordinates, you divide the subtraction of the y of the second point minus the y of the first point, by the subtraction of the x of the second point minus the x of the first point:
m = (yB-yA) / (xB-xA)
Let A(8,5) and B(6,7).
With yB = 7; yA = 5; xB = 6; xA = 8
m = (7-5) / (6-8)
m = 2/-2
m = -1
So the slope of the line that goes through the given points (8,5) and (6,7) is m = -1.
I've added a pic of the line with both points under the answer.
Hope this Helps! :)
Since the formula for the area of a circle is Pi x r squared, the area would be 81 x Pi (you teacher may want you to use Pi as 3.14 or put it in your calculator).