Odpowiedź:
[tex]q)\\\\\begin{cases}u=3t-2\\u=2t+3\end{cases}\\\\\\3t-2=2t+3\\\\3t-2t=3+2\\\\t=5\\\\\\u=3\cdot5-2=15-2=13\\\\\\\begin{cases}t=5\\u=13\end{cases}\\\\\\r)\\\\\begin{cases}t+2u=2\\3t-4u=11\end{cases}\\\\\\\begin{cases}t=2-2u\\3t-4u=11\end{cases}\\\\\\3(2-2u)-4u=11\\\\6-6u-4u=11\\\\-10u=11-6\\\\-10u=5\ \ /:(-10)\\\\u=-\frac{5}{10}\\\\u=-\frac{1}{2}\\\\\\t=2-2\cdot(-\frac{1}{2})=2+1=3[/tex]
[tex]\begin{cases}t=3\\u=-\frac{1}{2}\end{cases}\\\\\\t)\\\\\begin{cases}7a-b+17=0\\5a+6b=8\end{cases}\\\\\\\begin{cases}7a-b=-17\\5a+6b=8\end{cases}\\\\\\\begin{cases}-b=-17-7a\ \ /\cdot(-1)\\5a+6b=8\end{cases}\\\\\\\begin{cases}b=17+7a\\5a+6b=8\end{cases}\\\\\\5a+6(17+7a)=8\\\\5a+102+42a=8\\\\47a=8-102\\\\47a=-94\ \ /:47\\\\a=-2\\\\\\b=17+7\cdot(-2)=17-14=3\\\\\\\begin{cases}a=-2\\b=3\end{cases}[/tex]
[tex]u)\\\\\begin{cases}2s-t=5\\3s=t-6\end{cases}\\\\\\\begin{cases}-y=5-2s\ \ /\cdot(-1)\\3s-t=-6\end{cases}\\\\\\\begin{cases}t=-5+2s\\3s-t=-6\end{cases}\\\\\\3s-(-5+2s)=-6\\\\3s+5-2s=-6\\\\s=-6-5\\\\s=-11\\\\\\t=-5+2\cdot(-11)=-5-22=-27\\\\\\\begin{cases}s=-11\\t=-27\end{cases}[/tex]
