If r+4& 6 3& 3 = 5 & r+5 +2& 4 then r= - Vidyadip

MCQ

If $\begin{bmatrix}\text{r}+4&\text{amp; 6}\\3&\text{amp; 3}\end{bmatrix}=\begin{bmatrix}{5}&\text{amp;}\text{ r}+5\\\text{r+2}&\text{amp; 4}\end{bmatrix}$ then $\text{r}=$

✓
$1$
B
$2$
C
$3$
D
$-1$

✓

Answer

Correct option: A.

$1$

We know that two matrices are equal iff their corresponding elements are equal.
Thus comparing corresponding elements we get, for the first entry of.
the given matrices $r + 4 = 5$ and $r$ is satisfying other equations which are involving $r$
$ \Rightarrow r = 1$

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