Answer : value of x and y in the matrix equation is:
x = -3
y = +4, -4
Step-by-step explanation :
The matrix expression is:
[tex]\left[\begin{array}{ccc}x+4\\y^2+1\end{array}\right]+\left[\begin{array}{ccc}-9x\\-17\end{array}\right]=\left[\begin{array}{ccc}28\\0\end{array}\right][/tex]
First we have to add left hand side matrix.
[tex]\left[\begin{array}{ccc}(x+4)+(-9x)\\(y^2+1)+(-17)\end{array}\right]=\left[\begin{array}{ccc}28\\0\end{array}\right][/tex]
Now we have to add left hand side terms.
[tex]\left[\begin{array}{ccc}x+4-9x\\y^2+1-17\end{array}\right]=\left[\begin{array}{ccc}28\\0\end{array}\right][/tex]
[tex]\left[\begin{array}{ccc}4-8x\\y^2-16\end{array}\right]=\left[\begin{array}{ccc}28\\0\end{array}\right][/tex]
Now we have to equating left hand side matrix to right hand matrix, we get:
[tex]\Rightarrow 4-8x=28\text{ and }y^2-16=0\\\\\Rightarrow 8x=4-28\text{ and }y^2=16\\\\\Rightarrow x=-3\text{ and }y=\pm 4[/tex]
Therefore, the value of x and y in the matrix equation is -3 and +4, -4 respectively.
Answer:
D is wrong. The correct answer choice is C ( x=-3 and y= +4, -4)
Step-by-step explanation:
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