Answer:
Step-by-step explanation:
Ok this is pretty simple. Slope intercept is by far the most simple way to write an equation given that it only has 2 pieces: the slope of the line and the value at which it crosses the y axis (so when x=0). Slope is usually represented by the varriable "m" and the y intercept is usually represented by the letter "b". (Don't ask me why they chose these 2 random letters. It's... it's just whatever... Go with it.) Thus, we have the equation y=mx+b. So anyways.. Slope is just the change in y divided by the change in x. To find this, we just take 2 random points on the graph, subtract the first y from the second y and divide that by the first x subtracted from the second x. Let's use (2,-9) and (4,-10) from this fun little graph you ever so generously provided for us.
I'm bad at transitions so here's the math:
(y2-y1)/(x2-x1)
((-10)-(-9))/(4-2)
-1/2 ------> Thats "m".
SOOO... the slope is -1/2. Cool. BUT WE ARENT DONE
The other thing we need is the y-intercept. You may find yourself asking "what is this... this THING... he speaks of?" Its where the line hits the y axis. Thats is. It's not that hard. In this case it's -8 so b=-8.
Now for the best part... LETS PLUG ALL THOSE DOOHICKEYS IN.
y=mx+b
m=-1/2
b=-8
y=-1/2x+-8-----> y=-1/2x-8
TA DA
MAGIC
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