Уравнение прямой по двум точкам записывается в виде
![\frac{x-x_A}{x_B-x_a}=\frac{y-y_A}{y_B-y_A} \frac{x-x_A}{x_B-x_a}=\frac{y-y_A}{y_B-y_A}](https://tex.z-dn.net/?f=%5Cfrac%7Bx-x_A%7D%7Bx_B-x_a%7D%3D%5Cfrac%7By-y_A%7D%7By_B-y_A%7D)
где
- координаты точек.
0\Rightarrow7x+9y+6\geq0" alt="\frac{x-(-6)}{3-(-6)}=\frac{y-4}{-3-4}\\\frac{x+6}{9}=\frac{4-y}7\\7x+42=36-9y\\7x+9y+6=0\;-\;KM\\C(1;\;2)\Rightarrow7\cdot1+9\cdot2+6=7+18+6=31>0\Rightarrow7x+9y+6\geq0" align="absmiddle" class="latex-formula">
![\frac{x-3}{1-3}=\frac{y-(-3)}{2-(-3)}\\\frac{3-x}2=\frac{y+3}5\\15-5x=2y+6\\5x+2y-9=0\;-\;MC\\K(-6;\;4)\Rightarrow5\cdot(-6)+2\cdot4-9=-30+8-9=-31<0\Rightarrow5x+2y-9\leq0 \frac{x-3}{1-3}=\frac{y-(-3)}{2-(-3)}\\\frac{3-x}2=\frac{y+3}5\\15-5x=2y+6\\5x+2y-9=0\;-\;MC\\K(-6;\;4)\Rightarrow5\cdot(-6)+2\cdot4-9=-30+8-9=-31<0\Rightarrow5x+2y-9\leq0](https://tex.z-dn.net/?f=%5Cfrac%7Bx-3%7D%7B1-3%7D%3D%5Cfrac%7By-%28-3%29%7D%7B2-%28-3%29%7D%5C%5C%5Cfrac%7B3-x%7D2%3D%5Cfrac%7By%2B3%7D5%5C%5C15-5x%3D2y%2B6%5C%5C5x%2B2y-9%3D0%5C%3B-%5C%3BMC%5C%5CK%28-6%3B%5C%3B4%29%5CRightarrow5%5Ccdot%28-6%29%2B2%5Ccdot4-9%3D-30%2B8-9%3D-31%3C0%5CRightarrow5x%2B2y-9%5Cleq0)
![\frac{x-1}{-6-1}=\frac{y-2}{4-2}\\\frac{1-x}7=\frac{y-2}2\\2-2x=7y-14\\2x+7y-16=0\;-\;KC\\M(3;\;-3)\Rightarrow2\cdot3+7\cdot(-3)-16=6-21-16=-31<0\Rightarrow2x+7y-16\leq0 \frac{x-1}{-6-1}=\frac{y-2}{4-2}\\\frac{1-x}7=\frac{y-2}2\\2-2x=7y-14\\2x+7y-16=0\;-\;KC\\M(3;\;-3)\Rightarrow2\cdot3+7\cdot(-3)-16=6-21-16=-31<0\Rightarrow2x+7y-16\leq0](https://tex.z-dn.net/?f=%5Cfrac%7Bx-1%7D%7B-6-1%7D%3D%5Cfrac%7By-2%7D%7B4-2%7D%5C%5C%5Cfrac%7B1-x%7D7%3D%5Cfrac%7By-2%7D2%5C%5C2-2x%3D7y-14%5C%5C2x%2B7y-16%3D0%5C%3B-%5C%3BKC%5C%5CM%283%3B%5C%3B-3%29%5CRightarrow2%5Ccdot3%2B7%5Ccdot%28-3%29-16%3D6-21-16%3D-31%3C0%5CRightarrow2x%2B7y-16%5Cleq0)
Система неравенств, определяющих треугольник:
![\begin{cases}7x+9y+6\geq0\\5x+2y-9\leq0\\2x+7y-16\leq0\end{cases} \begin{cases}7x+9y+6\geq0\\5x+2y-9\leq0\\2x+7y-16\leq0\end{cases}](https://tex.z-dn.net/?f=%5Cbegin%7Bcases%7D7x%2B9y%2B6%5Cgeq0%5C%5C5x%2B2y-9%5Cleq0%5C%5C2x%2B7y-16%5Cleq0%5Cend%7Bcases%7D)