<span>-2x^2 + 10x + 9 =0
multiply whole equation by -1
2x^2 -10x -9 =0
(sqrt2x)^2 -2(sqrt2x)(5/</span>sqrt2) -9=0
add (5/sqrt2)^2 on both sides
(sqrt2x)^2 -2(sqrt2x)(5/sqrt2) + (5/sqrt2)^2-9=(5/sqrt2)^2
a^2-2ab+b^2=(a-b)^2
(sqrt2x - 5/sqrt2)^2=(5/sqrt2)^2+9
(sqrt2x - 5/sqrt2)^2=21.5
taking squareroot on both sides
sqrt2x - 5/sqrt2 = +-4.64
so
sqrt2x - 5/sqrt2 = +4.64 or sqrt2x - 5/sqrt2 = -4.64
sqrt2x = 4.64 + 5/sqrt2 sqrt2x = -4.64 + 5/sqrt2
sqrt2x =8.18 sqrt2x = -1.1045
x=8.18/sqrt2 x= -1.1045/sqrt2
x=5.78 x=-0.781
Answer:
B
Step-by-step explanation:
The practice of tacking 9/10 of a cent on the end of a gas price goes back to when gas cost only pennies per gallon and was a tax imposed by state and federal governments. Gas stations added the fraction of a cent on the end of the price instead of rounding up the price.
I don't know if I'm correct, I'm guessing... 30
The inequality that represents the domain of the function is
<h3>How to determine the domain?</h3>
The function is given as:
Set the radicand greater than or equal to 0
Multiply through by 2
x - 20 ≥ 0
Add 20 to both sides
x ≥ 20
Hence, the domain of the function is x ≥ 20
Read more about domain at:
brainly.com/question/1770447
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