I'm guessing just to show that you did your work to get the answer.
A
using the Cosine rule in ΔSTU
let t = SU, s = TU and u = ST, then
t² = u² + s² - (2us cos T )
substitute the appropriate values into the formula
t² = 5² + 9² - (2 × 5 × 9 × cos68° )
= 25 + 81 - 90cos68°
= 106 - 33.71 = 72.29
⇒ t = 
≈ 8.5 in → A
correct Option is B i.e, 
whose simplified form is: 
Step-by-step explanation:
We need to solve the expression:
![2[(6x)(6x)]+4[(12x - 9)(6x)]](https://tex.z-dn.net/?f=2%5B%286x%29%286x%29%5D%2B4%5B%2812x%20-%209%29%286x%29%5D)
Solving:
![2[(6x)(6x)]+4[(12x - 9)(6x)]\\=2[36x^2]+4[(12x*6x)-(9*6x)]\\=72x^2+4[72x^2-54x]\\=72x^2+288x^2-216x\\=360x^2-216x](https://tex.z-dn.net/?f=2%5B%286x%29%286x%29%5D%2B4%5B%2812x%20-%209%29%286x%29%5D%5C%5C%3D2%5B36x%5E2%5D%2B4%5B%2812x%2A6x%29-%289%2A6x%29%5D%5C%5C%3D72x%5E2%2B4%5B72x%5E2-54x%5D%5C%5C%3D72x%5E2%2B288x%5E2-216x%5C%5C%3D360x%5E2-216x)
So, correct Option is B i.e, whose simplified form is:
Keywords: Surface area of the rectangular prism
Learn more about surface area of the rectangular prism at:
#learnwithBrainly
9514 1404 393
Answer:
2√30 ∠-120°
Step-by-step explanation:
The modulus is ...
√((-√30)² +(-3√10)²) = √(30 +90) = √120 = 2√30
The argument is ...
arctan(-3√10/-√30) = arctan(√3) = -120° . . . . a 3rd-quadrant angle
The polar form of the number can be written as ...
(2√30)∠-120°
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<em>Additional comments</em>
Any of a number of other formats can be used, including ...
(2√30)cis(-120°)
(2√30; -120°)
(2√30; -2π/3)
2√30·e^(i4π/3)
Of course, the angle -120° (-2π/3 radians) is the same as 240° (4π/3 radians).
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At least one app I use differentiates between (x, y) and (r; θ) by the use of a semicolon to separate the modulus and argument of polar form coordinates. I find that useful, as a pair of numbers (10.95, 4.19) by itself does not convey the fact that it represents polar coordinates. As you may have guessed, my personal preference is for the notation 10.95∠4.19. (The lack of a ° symbol indicates the angle is in radians.)
THis would be 62 / 0.56 = 110.71 to nearest hundredth
