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Need Help!!!!! solving these problems

Need Help!!!!! solving these problems-example-1

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I'll tell you how to do the first exercise, since they all apply the same logic. Only the numbers will be different from time to time, so if you understand how to do the first one, you'll be able to do as many other as you want.

All these expressions are in the form


y=mx+q

which means that they represent a line. To draw a line, it is sufficient to draw two of its point. Then you can connect them with a segment, and extend the segment beyond the endpoints.

So, we simply need to sample two points from each equation. A point is a couple of coordinate
(x,y). The equation tells us in which relationship they have to be. So, you can arbitrarily choose two x values, and compute the corresponding y values. It is usually a good idea to use "easy", i.e. small, x values, to make computations easier.

So, for the first equation, let's choose the values x=0 and x=1, and see the corresponding y values. If we choose x=0, we have


y = -3\cdot 0 + 4 = 4 \implies P_1 = (0,4)

And if we choose x=1, we have


y = -3\cdot 1 + 4 = 1 \implies P_2 = (1,1)

Now, draw the two points on a coordinate plane and connect them, and you have your line.

User Gareth Farrington
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