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tekilochka [14]
3 years ago
14

Use Cramer’s rule to solve for x: x + 4y − z = −14 5x + 6y + 3z = 4 −2x + 7y + 2z = −17

Mathematics
2 answers:
nata0808 [166]3 years ago
8 0

Answer:

Solve using determinants:

x + 4y − z = −14  

5x + 6y + 3z = 4  

−2x + 7y + 2z = −17  

|A| =  -120  

|Ax| =  -240

|Ay| = 360  

|Az| = -480  

x =  2

y = -3    

z =  4

Step-by-step explanation:

Solving a 3 x 3 Linear System Using Cramer's Rule

sweet-ann [11.9K]3 years ago
7 0

Answer:

A = -120

AX = -240

X = 2

Step-by-step explanation:

∵ x + 4y - z = -14

∵ 5x + 6y + 3z = 4

∵ -2x + 7y + 2z = -17

\left[\begin{array}{ccc}1&4&-1\\5&6&3\\-2&7&2\end{array}\right]=\left[\begin{array}{ccc}-14\\4\\-17\end{array}\right]

∴ A = 1(6×2 - 3×7) + (-4)(2×5 - 3×-2) + (-1)(5×7 - 6×-2)

∴ A = 1(12 - 21) + (-4)(10 - -6) + (-1)(35 - -12)

∴ A = -9 + (-4)(16) + (-1)(47) = -9 - 64 - 47 = -120

To find X replace the column of X by the column of the answer

\left[\begin{array}{ccc}-14&4&-1\\4&6&3\\-17&7&2\end{array}\right]

∴ AX = -14(6×2 - 3×7) + (-4)(4×2 - 3×-17) + (-1)(4×7 - 6×-17)

∴ AX = -14(12 - 21) + (-4)(8 - -51) + (-1)(28 - -102)

∴ AX = 126 + (-4)(59) + (-1)(130) = 126 - 236 - 130 = -240

∴ X = AX/A = -240/-120 = 2

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sp2606 [1]

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Step-by-step explanation:

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2 years ago
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Answer:

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Step-by-step explanation:

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2 years ago
Ian has 12.2 ounce bottle of ketchip. He uses 1/20 of the ketchup every time he has a buffalo burger How many ounces of ketchup
tatiyna
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So, r is equal to 6.
7 0
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