Answer:
multiply the left side of the constant vector by the inverse matrix
Step-by-step explanation:
The matrix equation ...
AX = B
is solved by left-multiplying by the inverse of A:
A⁻¹AX = A⁻¹B
IX = A⁻¹B . . . . . the result of multiplying A⁻¹A is the identity matrix
X = A⁻¹B . . . . . B needs to be multiplied by the inverse matrix
![\left[\begin{array}{c}x&y\end{array}\right] = \left[\begin{array}{cc}-4&1\\3&2\end{array}\right]^{-1}\left[\begin{array}{c}9&7\end{array}\right]=\dfrac{1}{11}\left[\begin{array}{cc}-2&1\\3&4\end{array}\right]\left[\begin{array}{c}9&7\end{array}\right]=\left[\begin{array}{c}-1&5\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7Dx%26y%5Cend%7Barray%7D%5Cright%5D%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D-4%261%5C%5C3%262%5Cend%7Barray%7D%5Cright%5D%5E%7B-1%7D%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D9%267%5Cend%7Barray%7D%5Cright%5D%3D%5Cdfrac%7B1%7D%7B11%7D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D-2%261%5C%5C3%264%5Cend%7Barray%7D%5Cright%5D%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D9%267%5Cend%7Barray%7D%5Cright%5D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D-1%265%5Cend%7Barray%7D%5Cright%5D)
Answer: A
Step by step explaining:
4.25x4.25x4.25=
76.76
Then if you round it would get you to your answer.
Take Saturdays total of $620 and subtract Fridays total of $460 to get $160. Divide that by the difference of the number of pies sold on Friday and Saturday to get $8. Take the $8 and multiply by number of pies sold on Friday (20) to get $160. Take that number and subtract it from the total sold on Friday ($460) to get $300. Divide that by how many cakes were sold on Friday (30) and get $10.
So therefore:
Pies - $8 each
Cakes - $10 each
Answer would be 120 servings because 1 3/5 times 10 is 16, so I need to multiply 10 with 12 which is 20 the answer.
Answer:
x=13,y=39
Step-by-step explanation:
y=3x,x+y=52
x+3x=52
4x=52
x=52/4
x=13
y=3(13)
y=39