The last equation is the most suitable one to be solved by completing the square .
First, find the slope between the two points.
Slope = y2-y1 / x2-x1
-4+3/ -12+9
-1/-3
1/3 is the slope of this equation.
You do not have to go any further to find b or the y-intercept because it appears that b or the y-intercept is 0 in this case.
y= 1/3x or in other words y= x/3
18cm you multiple it my the figure given
Hey!
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Find what 44/7 is in a decimal.
44/7 = 6.285714...
We can see that it can lie between 6 and 7.
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Hope This Helped! Good Luck!
Zero point nine hundred and fourteen seven
^_^
Hope this helps you!