Expert: Sherman D. - 9/4/2004

Question
1) which of the following points are on the graph of -5x+ 4y = 18?
a)(-1.2, 3.0) b) (3,-3/4) c) (-18, 24) d) (-6, -3) e) (3.6, 9)
2) graph the equation. label the origin and the x and y -intercepts as O, P, and Q respectively. Find the area of Triangle OPQ.

Answer
-5x + 4y = 18
4y = 5x + 18
y = (5/4)x + (9/2)

a.)
(-1.2,3)
3 = (5/4)(-1.2) + (9/2)
3 = -1.5 + 4.5
3 = 3
A is True

b.)
(3,(-3/4))
(-3/4) = (5/4)(3) + (9/2)
(-3/4) = (15/4) + (9/2)
(-3/4) = (15/4) + (18/4)
(-3/4) = (33/4)
B is False

c.)
(-18,24)
24 = (5/4)(-18) + (9/2)
24 = -22.5 + 4.5
24 = -18
C is False

d.)
(-6,-3)
-3 = (5/4)(-6) + (9/2)
-3 = (-30/4) + (9/2)
-3 = (-15/2) + (9/2)
-3 = (-6/2)
-3 = -3
D is True

e.)
(3.6,9)
9 = (5/4)(3.6) + (9/2)
9 = 4.5 + 4.5
9 = 9
E is True

So the answer is A, D, and E

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as far as 2 goes, you did not give me any equations other than the one in #1.

since i don't have the equations i can't tell you the origin or the x and y intercepts. I also can't find the area since i don't know the dimensions, but as soon as i can find the vertices, i can find the dimensions, then i can find the area. Depending on what the dimensions are will depend on what the formula for the area is.