SOLUTION: FIND THE BASE AND HEIGHT OF A TRIANGLE area=60sq units base= 3x+6 height= x+5 area=1/2 bh help???

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Question 242054: FIND THE BASE AND HEIGHT OF A TRIANGLE
area=60sq units base= 3x+6 height= x+5
area=1/2 bh help???
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
FIND THE BASE AND HEIGHT OF A TRIANGLE
area=60sq units base= 3x+6 height= x+5
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Area = (1/2)bh
60 = (1/2)(3x+6)(x+5)
(3x+6)(x+5) = 120
3x^2 + 15x + 6x + 30 = 120
3x^2 + 21x - 90 = 0
x^2 + 7x - 30 = 0
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x = [-7 +- sqrt(49 - 4*-30)]/2
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x = [-7 +- sqrt(169)]/2
Positive Solution:
x = (-7 + 13]/2
x = 3
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base = 3x+6 = 3*3+6 = 15 units
height = x+5 = 3+5 = 8 units
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Cheers,
Stan H.