Answer: 
Step-by-step explanation:
Equilateral triangle has equal sides, let the side be
, then the perimeter is 
Therefore:



To find the altitude , we will apply Pythagoras theorem , that is

Therefore:



take the square root of both sides

420+86+109=615 I hope this helps you
Answer: 240 people get the news from social media
Step-by-step explanation:
The ratio of the number of people who get their news from social media to the number of people who their news elsewhere is 3:7
Total ratio is the sum of the proportion of those that get their news from social media and those that got their news elsewhere.
It becomes 3+7 = 10
Total number of people in the town is 800
To determine the number of people that got their news from social media, we will divide the proportion of those that get their news from social media by the total ratio and multiply by the total number of people in the town. It becomes
3/10 × 800 = 240
For this problem, let x be the number of children and y for adults. Formulate the equations: 1st equation, x + y = 3,200 and 2nd equation 5x + 9y = 24,000. Re-arrange 1st equation into x = 3200 - y. Then, substitute into 2nd equation, 5(3,200-y) + 9y = 24,000. Then, solve for y. The 16,000 - 5y + 9y = 24000. Final answer is, y = 2000 adults went to watch the movie.
Answer:
A
Step-by-step explanation:
This explanation mostly depends on what you're learning right now. The first way would be to convert this matrix to a system of equations like this.
g + t + k = 90
g + 2t - k = 55
-g - t + 3k = 30
Then you solve using normal methods of substitution or elimination. It seems to me that elimination is the quickest method.
g + t + k = 90
-g - t + 3k = 30
____________
0 + 0 + 4k = 120
4k = 120
k = 30
No you can plug this into the first two equations
g + t + (30) = 90
g + t = 60
and
g + 2t - (30) = 55
g + 2t = 85
now use elimination again by multiplying the first equation by -1
g + 2t = 85
-g - t = -60
_________
0 + t = 25
t = 25
Now plug those both back into one of the equations. I'll just do the first one.
g + (25) + (30) = 90
g = 35
Therefore, we know that Ted spent the least amount of time on the computer.
The second method is using matrix reduction and getting the matrix in the row echelon form, therefore solving using the gauss jordan method. If you would like me to go through this instead, please leave a comment.