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:
You forgot to post your mistake.
Step-by-step explanation:
Let x represent the amount of money you originally had. The algebraic expression would be: x-20+3×=80.
If you want to solve the equation, it would be: 4x=100, and x=100÷4, which equals 25. So your original money was $25.
a circle with a diameter of 2cm has a circumference of 6.28 cm
Answer:
0
Step-by-step explanation:
