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<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:
c
Step-by-step explanation:
because all the x values in c are different
Answer: Its the first and third one.
Step-by-step explanation: Lol nope
Answer:
D
Step-by-step explanation:
when flipping and turning the second triangle, so that it is oriented as the first triangle (we see DE corresponds to AB - consider at what corner point the right angle is : at A and at D; DF corresponds to AC, EF corresponds to BC), we see immediately that BCA is the same sequence of corners as the corresponding EFD.
