Zadanie 7 :
{2x - y = 5
{3(x - 1) + 2y = 1
{2x - y = 5
{3x - 3 + 2y = 1
{2x - y = 5 / * 2
{3x + 2y = 4
{4x - 2y = 10
+ {3x + 2y = 4
--------------------
7x = 14 / : 7
x = 2
2 * 2 - y = 5
4 - y = 5
y = -1
Zadanie 8 :
a)
[tex] \frac{3}{5 \sqrt{2} } \times \frac{ \sqrt{2} }{ \sqrt{2} } = \frac{3 \sqrt{2} }{5 \sqrt{ {2}^{2} } } = \frac{3 \sqrt{2} }{10} [/tex]
b)
w załączniku
Zadanie 9 :
[tex] \sqrt{12} + \sqrt{75} - \sqrt{48} + 2 \sqrt{3} = \\ \\ = \sqrt{4 \times 3} + \sqrt{25 \times 3} - \sqrt{16 \times 3} + 2 \sqrt{3} = \\ \\ = 2 \sqrt{3} + 5 \sqrt{3} - 4 \sqrt{3} + 2 \sqrt{3} = 5 \sqrt{3} [/tex]
