Answer:
The answer is below
Step-by-step explanation:
The system of equations:
8x-9y+13z=11
-8x-5y+5z=15
3x+4y-8z=-10
The equations can be represented in matrix form as:
AX = B
X = A⁻¹B
Therefore:
![\left[\begin{array}{ccc}8&-9&13\\-8&-5&5\\3&4&-8\end{array}\right] \left[\begin{array}{c}x\\y\\z\end{array}\right] =\left[\begin{array}{c}11\\15\\-10\end{array}\right]\\\\\\\left[\begin{array}{c}x\\y\\z\end{array}\right]=\left[\begin{array}{ccc}8&-9&13\\-8&-5&5\\3&4&-8\end{array}\right] ^{-1}\left[\begin{array}{c}11\\15\\-10\end{array}\right]\\](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D8%26-9%2613%5C%5C-8%26-5%265%5C%5C3%264%26-8%5Cend%7Barray%7D%5Cright%5D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7Dx%5C%5Cy%5C%5Cz%5Cend%7Barray%7D%5Cright%5D%20%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D11%5C%5C15%5C%5C-10%5Cend%7Barray%7D%5Cright%5D%5C%5C%5C%5C%5C%5C%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7Dx%5C%5Cy%5C%5Cz%5Cend%7Barray%7D%5Cright%5D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D8%26-9%2613%5C%5C-8%26-5%265%5C%5C3%264%26-8%5Cend%7Barray%7D%5Cright%5D%20%5E%7B-1%7D%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D11%5C%5C15%5C%5C-10%5Cend%7Barray%7D%5Cright%5D%5C%5C)
![\left[\begin{array}{c}x\\y\\z\end{array}\right]=\left[\begin{array}{ccc}\frac{1}{19} &-\frac{1}{19}&\frac{1}{19}\\-\frac{49}{380}&-\frac{103}{380}&-\frac{36}{95} \\-\frac{17}{380}&-\frac{69}{380}&-\frac{28}{95} \end{array}\right] \left[\begin{array}{c}11\\15\\-10\end{array}\right]\\\\\\\left[\begin{array}{c}x\\y\\z\end{array}\right]=\left[\begin{array}{c}-0.74\\-1.69\\0.13\end{array}\right] \\](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7Dx%5C%5Cy%5C%5Cz%5Cend%7Barray%7D%5Cright%5D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D%5Cfrac%7B1%7D%7B19%7D%20%26-%5Cfrac%7B1%7D%7B19%7D%26%5Cfrac%7B1%7D%7B19%7D%5C%5C-%5Cfrac%7B49%7D%7B380%7D%26-%5Cfrac%7B103%7D%7B380%7D%26-%5Cfrac%7B36%7D%7B95%7D%20%5C%5C-%5Cfrac%7B17%7D%7B380%7D%26-%5Cfrac%7B69%7D%7B380%7D%26-%5Cfrac%7B28%7D%7B95%7D%20%5Cend%7Barray%7D%5Cright%5D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D11%5C%5C15%5C%5C-10%5Cend%7Barray%7D%5Cright%5D%5C%5C%5C%5C%5C%5C%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7Dx%5C%5Cy%5C%5Cz%5Cend%7Barray%7D%5Cright%5D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D-0.74%5C%5C-1.69%5C%5C0.13%5Cend%7Barray%7D%5Cright%5D%20%5C%5C)
Complete question :
A 48 inch board in to be cut into three pieces so that the second piece is twice as long as the first, and the third piece in 3 times as long as the first. If x represents the length of the first, find the lengths of all three
Answer:
Length of first piece = x = 8
Length of second = 2x = 8*2 = 16
Length of third = 3x = 8 * 3 = 24
Step-by-step explanation:
Let :
Length of first piece = x
Length of second = 2x
Length of third = 3x
The total lengtb of board = 48 inches
Hence,
First + second + third = 48
x + 2x + 3x = 48
6x = 48
x = 48 / 6
x = 8
Length of first piece = x = 8
Length of second = 2x = 8*2 = 16
Length of third = 3x = 8 * 3 = 24
X + y = 304,250
x = y + 51,000
Plug in (y+51,000) for x into the first equation
y+51,000+y = 304,250
Subtract 51,000 from both sides.
2y = 253,250
y = 126,625
Plug y into second equation
x = 126,625 + 51,000
x =177,625
Person A : 177,625
Person B : 126,625
Answer:
6
Step-by-step explanation:
66 divided by 11
Answer:1/4×l +(2 1/2) = 4
l = 6
Step-by-step explanation:For l laps around a 1/4 mile track, the total distance is ...
l×(1/4)
After adding 2 1/2 miles to that, Gabriella's total distance was 4 miles:
l×(1/4) +(2 1/2) = 4 . . . . an equation to find l
__
We can solve this equation by subtracting 2 1/2, then multiplying by 4.
l×(1/4) = 1 1/2
l = 4(1 1/2)
l = 6 hope it helps
