SOLUTION: I have a blank graph with a line going through the first quadrant. The points on the line are (4,2.2) and (5, 1.7). Determine the area of the Triangle. Man I am so lost!!

Algebra ->  Linear-equations -> SOLUTION: I have a blank graph with a line going through the first quadrant. The points on the line are (4,2.2) and (5, 1.7). Determine the area of the Triangle. Man I am so lost!!      Log On


   

Question 923934: I have a blank graph with a line going through the first quadrant. The points on the line are (4,2.2) and (5, 1.7). Determine the area of the Triangle. Man I am so lost!!
Found 2 solutions by josmiceli, stanbon:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
All you have to do is find the equation
of the line, then find the x and y
intercepts.
That gives you the legs of a rt. triangle,
so you can find area
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Use the general point-slope formula
+%28+y+-+1.7+%29+%2F+%28+x+-+5+%29+=+%28++2.2+-+1.7+%29+%2F+%28+4+-+5+%29+
+%28+y+-+1.7+%29+%2F+%28+x+-+5+%29+=+.5+%2F+%28-1%29+
+%28-1%29%2A%28+y+-+1.7+%29+=+.5%2A%28+x+-+5+%29+
+-y+%2B+1.7+=+.5x+-+2.5+
+y+=+-.5x+%2B+4.2+
check:
Does it go through ( 4,2.2 )?
+y+=+-.5x+%2B+4.2+
+2.2+=+-.5%2A4+%2B+4.2+
+2.2+=+-2+%2B+4.2+
+2.2+=+2.2+
OK- I'll assume the other point is OK
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So, now you have the point ( 0, 4.2 )
and also
( 8.4, 0 )
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The area is +%281%2F2%29%2Ab%2Ah+
+A+=+%281%2F2%29%2A4.2%2A8.4+
+A+=+17.64+
Check my math



Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
I have a blank graph with a line going through the first quadrant. The points on the line are (4,2.2) and (5, 1.7). Determine the area of the Triangle.
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Plot the two points and draw the line.
Draw a line segment connecting (4,0) to (4,2.2)
and a line segment connecting (5,0) to (5,1.7)
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Area = ?
Draw a horizontal line segment joining (5,1.7) to (4,1.7)
You now have a rectangle with base = (5-4) = 1 and height = 1.7.
Area of that rectangle is 1*1.7 = 1.7 sq units
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You also have a triangle with base = 1 and height = 2.2-1.7 = 0.5
Area of that triangle is (1/2)(1)(0.5) = 0.25 sq units
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Total Area = 1.7 + 0.25 = 1.95
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Cheers,
Stan H.
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