Answer: Choice B
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Explanation:
The given matrix is
![\left[\begin{array}{cc|c}1&5&11\\4&-6&-3\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7Cc%7D1%265%2611%5C%5C4%26-6%26-3%5Cend%7Barray%7D%5Cright%5D)
The numbers to the right of the vertical bar represent the values on the right hand side of each equation in the final answer.
The numbers to the left of the bar represent the x and y coefficients of the equations. The first number of any given row is the x coefficient. The second number is the y coefficient.
For instance, the first row has 
to indicate the x coefficient is 1, and the y coefficient is 5. We end up with 1x+5y or simply x+5y. Putting everything together, the first equation would be x+5y = 11
Through similar steps, the second equation is 4x-6y = -3
7.) Area of a square pyramid is given by A = s^2 + 2sl; where s is the side length of the base and l is the slant height.
Area of given pyramid = 4^2 + (2 x 4 x 7) = 16 + 56 = 72 ft^2
8.) Area of the given pyramid is the area of the hexagonal base plus the area of the six slant triangles.
Area of hexagonal base = (3sqrt(3))/2 x 10^2 = 150 x 1.732 = 259.8
Area of the 6 traingles = 6(1/2 x 10 x 13) = 6 x 65 = 390
Total surface area of the pyramid = 259.8 + 390 = 649.8 ≈ 650 m^2
9.) Using pythagoras rule, the slant height is sqrt(6^2 + 3.5^2) = sqrt(36 + 12.25) = sqrt(48.25) = 6.9 mm
10.) The surface area of a cone is given by πr^2 + πrl
Area = π x 6^2 + π x 6 x 20 = 36π + 120π = 490.1 cm^2
11.) l = sqrt(r^2 + h^2) = sqrt(11^2 + 16^2) = sqrt(121 + 256) = sqrt(377) = 19m
In any cyclic quadrilateral, angles opposite one another are supplementary, meaning
and given that 
, we have 
.
By the inscribed angle theorem,
and since
we have
and it follows that
Answer: y = 1.8
Step-by-step explanation:
xy = 12.6 If x is 7 but 7 in the equation for x
7y = 12.6 Divide both sides by 7
y = 1.8
