Question

va rog exercitiile 5 si 6

Answer 1

   
[tex]\displaystyle\\ 5)\\ x-2y+3=0\\ x=2y-2\\ \text{Dam valori lui y si il aflam pe x.}\\ y=1\Rightarrow x = 2 \cdot 1 - 3 = -1 \Rightarrow A(-1,~1)\\ y=3\Rightarrow x = 2 \cdot 3 - 3 = 3 \Rightarrow B(3,~3)\\ y=10\Rightarrow x = 2 \cdot 10 - 3 = 17 \Rightarrow B(17,~10)\\ \text{etc...etc...}\\\\ 6)\\ \sin a = \frac{3}{5} \\\\ \cos a = \sqrt{1-\sin^2a}= \sqrt{1-\left( \frac{3}{5} \right)^2}= \sqrt{1- \frac{9}{25} }= \sqrt{ \frac{25-9}{25} }=\sqrt{ \frac{16}{25} }=\frac{4}{5} [/tex]