Dear Mary) My students all want to see your lamb. If it isn't too much trouble, please bring your lamb to our school. Yes you may bring other lambs. No, the lamb does not need to be on a leash. We will prepare grains, grassjand hay for your lamb to eat. With thanks) Mrs. Kim

a) Find the Rank of the following Matrix by normal form \( \left[\begin{array}{cccc}2 & 3 & -1 & -1 \\ 1 & -1 & -2 & -4 \\ 3 & 1 & 3 & -2 \\ 2 & 3 & 1 & 1\end{array}\right] \)

\( \substack{\text { Ecuaciones lineales con } \\ \text { una incognita }} \) \( 8 x+7=-9 \)

If \( (3,6, y, 5)=(3,6, x, 7) \), what is the value of \( x-y \) ?

5. If \( A=\{3,5,7,9,10\}, B=\{7,9,10,13\} \) and \( C=\{10,13,16,15\} \) Find (i) \( |A \cap B| \) (2 marks) \( ->\{7,7\} \) (ii) \( A \cup B \cup C \) (2 marks) (iii) \( A \cap B \cup C \) (2 marks) (iv) Power set of \( C \) (2 marks) (v) \( B \triangle C \) (3 marks)

1. Résoudre les équations \( -4 x \equiv 14(\bmod 30) \) \( -2 x^{2}+(2+3 i) x+2 i-1=0 \) \( -3 x \equiv 4(\operatorname{modulo} 7) \)