Step-by-step explanation:
first u need to pick a random coordinate to substitute the X . example 0
y = 2(0) + 1
y =1 , X= 0
X= 1
y= 2(1) + 1
y= 3, X= 1
then you continue this same process and again until u have at least two points to draw a straight line. it kinda depended if u want to fill the entire graph.
Answer:
112 $ is the original price
Step-by-step explanation:

you have to think that the original price multiplied by 0.75 (also known as 75%) gave the result of what he saves i.e 84 $. So we put up an equation with the original price multiplied by 75% which equals the 84 $ he saved on buying that item on sale
M - 30 = 10
so the number has to be 10 more than 30.
30+ 10 = m
m = 40
X = y + 3
2x + y = 9
Solution..
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Substitute for x=y+3 in the second equation...
2x+y = 9
2(y+3)+y=9
2y+6+y=9
3y+6=9
3y=9-6
3y=3
y=3/3
y=1....
Substitute for y=1 in the first equation...
x=y+3
x = 1+3
x=4..
Am sure the answer is quite evident now...