document.write( "Question 59322This question is from textbook
\n" ); document.write( ": here's a table.
\n" ); document.write( "x y
\n" ); document.write( "4 14
\n" ); document.write( "8 15.5
\n" ); document.write( "12 17
\n" ); document.write( "16 18.5
\n" ); document.write( "i know the rate of change is 1.5, but how would i find the value of y when x=120?? how about finding the value of x when y=50?? \n" ); document.write( "
Algebra.Com's Answer #40661 by funmath(2933)\"\" \"About 
You can put this solution on YOUR website!
here's a table.
\n" ); document.write( "x y
\n" ); document.write( "4 14
\n" ); document.write( "8 15.5
\n" ); document.write( "12 17
\n" ); document.write( "16 18.5
\n" ); document.write( "How would i find the value of y when x=120?? how about finding the value of x when y=50??
\n" ); document.write( "Your rate of change is the slope between various points. I checked this out and this is indeed a linear relation.
\n" ); document.write( "The formula to find the slope between two points is:
\n" ); document.write( "\"highlight%28m=%28y2-y1%29%2F%28x2-x1%29%29\"
\n" ); document.write( "You can choose any two points to find the slope, so let's choose the ones without decimals to make it a little easier.
\n" ); document.write( "(x1,y1)=(4,14) and (x2,y2)=(12,17)
\n" ); document.write( "\"m=%2817-14%29%2F%2812-4%29\"
\n" ); document.write( "\"m=3%2F8\"
\n" ); document.write( "We can now find the equation of the line using the point-slope formula:\"highlight%28y-y1=m%28x-x1%29%29\", m=slope,(x1,y1)=any point on the line.
\n" ); document.write( "(x1,y1)=(4,14) and m=3/8
\n" ); document.write( "\"y-14=%283%2F8%29%28x-4%29\"
\n" ); document.write( "\"8%28y-14%29=8%283%2F8%29%28x-4%29\"
\n" ); document.write( "\"8y-112=3%28x-4%29\"
\n" ); document.write( "\"8y-112=3x-12\"
\n" ); document.write( "\"-3x%2B8y-112=-3x%2B3x-12\"
\n" ); document.write( "\"-3x%2B8y-112%2B112=112-12\"
\n" ); document.write( "\"-3x%2B8y=100\"
\n" ); document.write( "\"-%28-3x%2B8y%29=-100\"
\n" ); document.write( "\"3x-8y=-100\"
\n" ); document.write( ":
\n" ); document.write( "When x=120
\n" ); document.write( "3(120)-8y=-100
\n" ); document.write( "360-8y=-100
\n" ); document.write( "-360+360-8y=-360-100
\n" ); document.write( "-8y=-460
\n" ); document.write( "-8y/-8=-460/-8
\n" ); document.write( "y=115/2
\n" ); document.write( "\"highlight%28y=57.5%29\"
\n" ); document.write( ":
\n" ); document.write( "When y=50
\n" ); document.write( "3x-8(50)=-100
\n" ); document.write( "3x-400=-100
\n" ); document.write( "3x-400+400=400-100
\n" ); document.write( "3x=300
\n" ); document.write( "3x/3=300/3
\n" ); document.write( "\"highlight%28x=100%29\"
\n" ); document.write( ":
\n" ); document.write( "If I just blew your mind and you've never seen any of this before, another way you can do this is to plot the points on a graph and using graph paper and a ruler you can approximate the same thing.
\n" ); document.write( ":
\n" ); document.write( "Happy Calculating!!! \n" ); document.write( "
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