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 ⇒ r = 1

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