SOLUTION: Okay, i kinda asked a question like this earlier but i forgot one thing. A chart shows ideal heights and weights for adults with a medium build. A person with the height of 6o in

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Question 239045: Okay, i kinda asked a question like this earlier but i forgot one thing.
A chart shows ideal heights and weights for adults with a medium build. A person with the height of 6o inches should have a weight of 112 pounds and a person with the height of 66 inches should have a weight of 136.
Write a linear equation to estimate the weight of a person of any height.
HOW DO I DO THAT?
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
60 inches = 112 pounds
66 inches = 136 pounds

let x = inches and y = pounds

(x1,y1) = 60,112)
(x2,y2) = 66,136)

slope of straight line = y2-y1/(x2-x1) = (136-112)/(66-60) = 24/6 = 4

slope-intercept form of straight line equation is y = mx+b where m is the slope and b is the y-intercept.

your equation is y = 4x + b because it has a slope of 4.

substitute either one of the points (x1,y1) or (x2,y2) in the equation to solve for the y-intercept which is b.

equation of y = 4x + b becomes:

112 = 4*60 + b if we use (x1,y1).

solving for b we get:

112 = 240 + b
b = 112-240 = -128

equation becomes y = 4x - 128

graph of this equation looks like:

graph%28600%2C600%2C-10%2C100%2C-10%2C200%2C4x-128%2C112%2C136%29

the graph has y = 112 and 136 to show you that they occur at x = 60 and x = 66 as they should.

lso not very accurate although not quite as bad as on the low end.

If you restricted the domain for the value of x being from 50 to 70 then the graph straight line project might be ok.

Since this graph is a straight line calculated between only 2 points, it doesn't accurately portray the height to weight ratio at the extremes of the height range.