yes, the first one is right. "Exact" solution means to leave it in fractional form... Don't calculate what 9/5 is in decimals. (Although in this case, 9/5 is a terminating decimal, so it doesn't matter...)
4(y-2) = 10y + 5
4y - 8 = 10y + 5
-6y - 8 = 5
-6y = 13
y = -13/6
In this case, you would need to leave it as a fraction because the decimal is 2.16666 (with a repeating 6).
(2x-5)(x + 8) = 0
set each piece =0 and solve:
2x - 5 = 0
x = 5/2
and
x + 8 = 0
x = -8
x^2 - 2x - 8 = 0
(x - 4)(x + 2) = 0
x = 4, -2
8x^2 - 24 = 0
8x^2 = 24
x^2 = 3
x = (sqrt 3) and (- sqrt 3)
2007-06-07 03:21:36
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answer #1
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answered by Mathematica 7
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4y - 8 = 10y + 5
-6y = 13
y = 13/6
(2x - 5)(x + 8) = 0 has two solutions.
Either 2x - 5 = 0 (x = 5/2)
or x + 8 = 0 (x = -8)
x^2 - 2x - 8 = 0 is solved using the quadratic formula.
Given the equation ax^2 + bx + c = 0,
x = (-b +/- sqrt(b^2 - 4 * a * c)) / (2 * a)
Here, x = (2 +/- sqrt(4 + 32))/(2 * 2)
x = (2 +/- sqrt(36))/4
x = (2 +/- 6)/4
x = 8/4 or -4/4
x = 2 or -1
8x^2 = 24
x^2 = 3
x = +/- sqrt(3)
2007-06-07 03:24:18
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answer #2
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answered by TychaBrahe 7
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4(y-2)=10y+5
=>8y-8=10y+5
=>8y-10y=5+8
=> -2y=13
=>y=13/-2= -6.5
(2x-5)(x+8)=0
As the product of the two factors is zero,at least one of them must be zero
Therefore either 2x-5=0 or x+8=0
If 2x-5=0,then 2x=5 or x=5/2 or 2.5
If x+8=0,then x= -8
Hence x=2.5 or -8 ans
x^2-2x-8=0
=>x^2-4x+2x-8=0
=>x(x-4)+2(x-4)=0
=>(x-4)(x+2)=0
Therefore either x-4=0 or x+2=0
Hence x=4 or -2 ans
8x^2-24=0
=>8x^2=24
=> x^2=24/8=3
=>x= +/- sqrt 3 ans
2007-06-07 03:27:06
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answer #3
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answered by alpha 7
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4(y - 2) = 10y + 5
4y - 8 = 10y + 5
-8 = 6y + 5
-13 = 6y
y = -13/6
(2x - 5)(x + 8) = 0
2x - 5 = 0 x + 8 = 0
2x = 5 x = -8
x = 5/2
x = 5/2 , -8
x^2 - 2x - 8 = 0
(x - 4)(x + 2) = 0
x = 4, -2
8x^2 - 24 = 0
8x^2 = 24
x^2 = 3
x = +/- sqrt (3)
2007-06-07 03:21:00
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answer #4
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answered by hawkeye3772 4
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4(y-2)=10y+5
4y - 8 = 10y + 5
6y = -13
y = -13/6
(2x-5)(x+8)=0
2x - 5 = 0
x = 5/2
or
x + 8 = 0
x = -8
x^2-2x-8=0
(x - 4)(x + 2) = 0
x = 4
or
x = -2
8x^2-24=0
x^2 = 3
x = sqrt(3)
2007-06-07 03:22:45
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answer #5
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answered by blighmaster 3
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because of the fact the quantity is a hundred and twenty and the top of the field is 3, the part of the backside of the field is 40. There for the climate of the sq. base are the sq. root of 40. upload returned the 6 inches removed from the two facet and you have the unique dimensions.
2016-11-26 22:37:37
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answer #6
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answered by degraffenreid 4
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