SOLUTION: a rectangle is (x+3)cm long and y cm wide.the perimeter of the rectangle is 20cm
a)show that y=7-x
b)the area is 19cm^2. Show that x^2-4x-2=0
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-> SOLUTION: a rectangle is (x+3)cm long and y cm wide.the perimeter of the rectangle is 20cm
a)show that y=7-x
b)the area is 19cm^2. Show that x^2-4x-2=0
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Question 457588: a rectangle is (x+3)cm long and y cm wide.the perimeter of the rectangle is 20cm
a)show that y=7-x
b)the area is 19cm^2. Show that x^2-4x-2=0 Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! a rectangle is (x+3)cm long and y cm wide.
the perimeter of the rectangle is 20cm
a)show that y=7-x
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Perimeter = 2(length + width)
20 = 2(x+3 +y)
10 = x + 3 + y
y = 7-x
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b)the area is 19cm^2. Show that x^2-4x-2=0
Area = length*width
19 = (x+2)y
19 = (x+2)(7-x)
19 = -(x+2)(x-7)
19 = -[x^2-5x-14]
x^2 -5x-14+19 = 0
x^2 -5x +5 = 0
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Cheers,
Stan H.
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