gallla
28.01.2020 •
Mathematics
What is the area of this triangle?
enter your answer as a decimal in the box. round only your final answer to the nearest tenth.
Solved
Show answers
More tips
- F Family and Home Protect Your Home or Apartment from Pesky Ants...
- O Other What is a Disk Emulsifier and How Does it Work?...
- H Health and Medicine How to Calm Your Nerves? Expert Tips That Actually Work...
- A Animals and plants 5 Tips for Taking Care of Yews to Keep Them Green and Beautiful...
- S Sport How to wrap boxing hand wraps? Everything you need to know!...
- F Food and Cooking 10 Reasons Why You Should Avoid Giving Re-Gifts: An Informative Guide...
- F Family and Home Tender Care for Your Parquet: Is it Possible to Clean Parquet?...
- S Style and Beauty How Are Eyelash Extensions Applied? All Your Questions Answered...
- F Food and Cooking 10 Tips for Proper Sushi Consumption...
- S Style and Beauty Learn how to tie a keffiyeh on your head like a pro...
Answers on questions: Mathematics
- G Geography image by e2020 which of the earth’s two forest biomes are missing from the image above? a.coniferous and deciduousb.tropical and polarc.tropical and deciduousd.coniferous...
- L Law A đang là giám đốc công ty TNHH Hoa Mai; B đang là chủ Doanh nghiệp TN Bình Minh và C đang là nhân viên hợp đồng của sở GD&ĐT tỉnh Thái Nguyên muốn thành lập...
- M Mathematics Find the equation of straight line which cuts the x and y axis 4,9 units...
- M Mathematics Solve this triangle using the law of sines...
- M Mathematics Can someone help me?? Work out the surface area of this solid prism....
Ответ:
13.2
Step-by-step explanation:
First we find the missing side of the triangle using the law of cosines:
c² = a²+b²-2ab(cos C)
c² = 8²+7²-2(8)(7)(cos 28)
c² = 64+49-112(cos 28)
c² = 113-112(cos 28)
c² = 14.1099
√c² = √14.1099
c = 3.8
Next we use the law of sines to find the angle opposite the 7 cm side:
sin 28/3.8 = sin B/7
Cross multiply:
7(sin 28) = 3.8(sin B)
Divide both sides by 3.8:
7(sin 28)/3.8 = 3.8(sin B)/3.8
0.8648 = sin B
Take the inverse sine:
sin⁻¹(0.8648) = sin⁻¹(sin B)
60 = B
The height of the triangle will extend from the lowest vertex to the 8 cm side. This makes the right triangle formed to the left a 30-60-90 triangle. In these triangles, the side opposite the 90 degree angle is twice as much as the side opposite the 30 degree angle; this means the portion of the 8 cm side from the height to the left will be 3.8/2 = 1.9 cm.
Using the Pythagorean theorem with 1.9 as a leg and 3.8 as the hypotenuse,
1.9² + b² = 3.8²
3.61 + b² = 14.44
Subtract 3.61 from each side:
3.61 + b² - 3.61 = 14.44 - 3.61
b² = 10.83
Take the square root of each side:
√b² = √10.83
b = 3.3
This means the height of the triangle is 3.3. Using 8 as the base,
A = 1/2bh
A = 1/2(3.3)(8) = 13.2
Ответ:
The Principle of Zero Products states that if ab = 0, then either a = 0 or b = 0, or both a and b are 0. Once the polynomial is factored, set each factor equal to zero and solve them separately.