Answer:
Time machine one = 3.56
Time machine two = 4.56
Step-by-step explanation:
Let machine 2 do the job in x hours
Let machine 1 do the job in x - 1 hours.
The general formula for this problem is
Time = A*B/(A + B)
Givens
Time = 2 hours
B = x hours alone
A = x - 1 hours alone.
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x *( x - 1)
======= = 2
(x + x - 1)
(x^2 - x)/(2x - 1) = 2
x^2 - x = 2(2x - 1)
x^2 - x = 4x - 2
x^2 - 5x + 2 = 0
a = 1
b = - 5
c = 2
This gives 2 roots
x = 4.56
x = 0.43
The second root will not work because when 1 is subtracted from 0.43 the time give will be minus, which won't work.
Time for machine 2 is 4.56
The time for machine 1 is 3.56
Check
(A * B)/(A + B) = 2
A = 4.56
B = 3.56
Time = 4.56*3.56/(4.56 + 3.56)
Time = 16.2336/(8.12)
Time = 1.9992
The rounding error in the check comes from the rounding error in the times.
Answer: 296 is 74% of 400.
Answer:
it is correct
Step-by-step explanation:
Answer:
Step-by-step explanation:
x^3 - 8x² - x + 8 =0
x^3 - 8x² - (x - 8 )=0
x²(x-8) - (x-8) = 0
(x-8)(x² -1) =0
x-8 = 0 or x² - 1 = 0
x-8=0 or (x-1)(x+1)=0
x=8 x=1 or x=-1
The determinant of a 2 x 2 matrix can be calculated as:
Product of non-diagonal elements subtracted from product of diagonal elements.
The diagonal elements in given matrix are 12 and 2. The non-diagonal elements are -6 and 0.
So,
Determinant G = 12(2) - (-6)(0)
Determinant G = 24 - 0 = 24
So, option B gives the correct answer
