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43 votes
43 votes
I am soooo confuseddd what the heckkk Ok so Im doing something called 'Graphing Systems of Linear Equations' , well you might say its easy but I never understood something in the last lesson to begin with so this is like so freaking frustrating. Im looking at examples but it doesnt make sensssse help Ok so look at the screenshot. Why is one point on the line -4

and for the person who deleted my question lasttime, please stop. Try to see it from my perspective, Im desperate for homework help cuz obviously I don't want to fail and want to understand the lesson and get my homework done, checking to see if someone answered my question every 5 mins, and instead I see someone deleted it.

Please help???

-fellow student

I am soooo confuseddd what the heckkk Ok so Im doing something called 'Graphing Systems-example-1
User Pikovayadama
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1 Answer

17 votes
17 votes
Okay, so the equation for the y-intercept is y=mx+b, this will be your base for graphing anything.

For y = x + 3 it's basically y = 1x + 3. Use b as the y-intercept, or 3, and plot it as (x,y), (0,3). Then use m as the slope, or 1. 1 means positive one so the point goes (0,3), (1, 4), (2, 5).

For y = -3x - 1 it's the same thing but different numbers. Use b, the y-intercept, and plot it. -1 is b, so plot (0,-1). Then use the slope to go up or down the direction you need to go, or m. m is -3, so for every +1 in x, the y will decrease by 3. (0,-1), (0,-4), (0,-7).

I hope this helped in some way or increased your understanding!
User Miketreacy
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