Answer: x = ¹/₂ ± √⁸¹
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2
Step-by-step explanation:
First write out the equation
x² - x - 20
Now we now write the equation by equating to 0
x² - x - 20 = 0
We now move 20 to the other side of the equation. So
x² - x = 20,
We now add to both side of the equation square of the half the coefficient of the (x) and not (x²) which is (1) . So, the equation now becomes
x² - x + ( ¹/₂ )² = 20 + ( ¹/₂ )²
x² - ( ¹/₂ )² = 20 + ¹/₄
( x - ¹/₂ )² = 20 + ¹/₄, we now resolve the right hand side expression into fraction
( x - ¹/₂ )² = ⁸¹/₄ when the LCM is made 4
Taking the square root of both side to remove the square,we now have
x - ¹/₂ = √⁸¹/₄
x - ¹/₂ = √⁸¹/₂
Therefore,
x = ¹/₂ ± √⁸¹
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2
Answer:
223.2725
Step-by-step explanation:
223.2725
Answer:
r=201
d = 77 1/2
Step-by-step explanation:
6) First multiply left and right by 16, to get rid of the fraction:
r - 25 = 11*16
Now add 25 left and right:
r = 11*16 + 25 = 201
7) Add 5 left and right
2/5 d = 31
multiply by 5/2
d = 31 * 5/2 = 77 1/2
Answer:
a = 8, b = 
Step-by-step explanation:
Given the exponential function
f(x) = a
To find a and b use the given coordinate points on the graph
Using (0, 8 ), then
8 = a
[ = 1 ] , then
a = 8
f(x) = 8
Using (2, 18 ) , then
18 = 8b² ( divide both sides by 8 )
= b² , that is
b² = 
( take the square root of both sides )
b = 
=
Thus
f(x) = 8
