Answer:
After completing the square the expression is (x-2)^2 -12 =0 and real solution are x = 5.46 and x = -1.46
Step-by-step explanation:
We need to complete the square:
x^2 − 4x − 8 = 0
x^2 -2(x)(2)+(2)^2 -8 -4 =0
(x^2 -4x +4) - 12 = 0
(x-2)^2 -12 =0
Now, finding the value of x
(x-2)^2 -12 =0
(x-2)^2 = 12
taking square root on both sides
So, After completing the square the expression is (x-2)^2 -12 =0 and real solution are x = 5.46 and x = -1.46
This isn't a math question and should be in the science section. However, I will still answer the question. The answer is choice B.
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Here's a further breakdown
A. False. The radiation or energy from the sun can travel through air or else you wouldn't feel the sun's rays. Also, plant life wouldn't be alive without that energy going through the air.
B. True. The rays travel through a vacuum of space. If they couldn't travel through space, then the same problem comes up as in choice A: the issue of not feeling the sun's rays.
C. False. They rays have different frequencies. Because there are many wavelengths (see choice D below), this means there are different frequencies. Recall that f = 1/w where f is the frequency and w is the wavelength.
D. False. The rays are made of different wavelengths. The visible light portion is what we can see, though there is a lot more to the electromagnetic spectrum (eg: ultraviolet light).
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So once again, the answer is choice B
The formula for finding time is the distance divided by the velocity.So the answer is 100÷30=3.3333...
Answer:
1st pic:
step 2.
2nd pic:
Rene should add, not multiply 2 volumes.
The correct answer is 48+216 =264
3rd pic:
a, for blue prism: V = Area of base x Height = 48 x a =720
=> a = 720/48 = 15
b, for orange prism: V = Area of base x Height = (12xb)/2 x 15 =720
=> b =(720x2)/(15x12)= 8
A and B are correct... reason is because hundredths is 1/10 to tenths and tenths are 10 times bigger than hundredths. C and D are wrong.
Hope this helped!
Nate
