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This assignment is due is half an hour and I'm really lost

This assignment is due is half an hour and I'm really lost-example-1
User Biggdman
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1 Answer

4 votes

Answer:


3B - 4C = \left[\begin{array}{cc}-8 &-23\\1&-15\end{array}\right]

Step-by-step explanation:

Given


B = \left[\begin{array}{cc}8&-5\\-1&3\end{array}\right]


C = \left[\begin{array}{cc}8&2\\-1&6\end{array}\right]

Required

Determine 3B - 4C

If


B = \left[\begin{array}{cc}8&-5\\-1&3\end{array}\right]

Then


3B = 3 * \left[\begin{array}{cc}8&-5\\-1&3\end{array}\right]


3B = \left[\begin{array}{cc}24&-15\\-3&9\end{array}\right]

Similarly,

If


C = \left[\begin{array}{cc}8&2\\-1&6\end{array}\right]

Then


4C = 4 * \left[\begin{array}{cc}8&2\\-1&6\end{array}\right]


4C = \left[\begin{array}{cc}32&8\\-4&24\end{array}\right]

So:


3B - 4C = \left[\begin{array}{cc}24&-15\\-3&9\end{array}\right] - \left[\begin{array}{cc}32&8\\-4&24\end{array}\right]

This gives:


3B - 4C = \left[\begin{array}{cc}24 - 32 &-15-8\\-3-(-4)&9-24\end{array}\right]


3B - 4C = \left[\begin{array}{cc}-8 &-23\\1&-15\end{array}\right]

User Eve Freeman
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