Find the area of the triangle formed by the lines x = 0, y = 1 and 2x + y = 2.
The given equations are
$x=0 \ldots(\mathrm{i})$
$y=1 \ldots(\mathrm{ii})$
and $2 x+y=2 \ldots$ (iii)
Let eq. (i), (ii) and (iii) represents the sides AB, BC and AC respectively of ΔABC
From eq. (i) and (ii), we get $x=0$ and $y=1$
Thus, $A B$ and $B C$ intersect at $(0,1)$
Solving eq. (ii) and (iii), we get
$y=1 \ldots$ (ii)
and $2 x+y=2 \ldots$ (iii)
Putting the value of y = 1 in eq. (iii), we get
$2 x+1=2$
$\Rightarrow 2 x=1$
$\Rightarrow x=\frac{1}{2}$
Thus, $\mathrm{BC}$ and $\mathrm{AC}$ intersect at $\left(\frac{1}{2}, 1\right)$
Now, Solving eq. (iii) and (i), we get
$2 x+y=2 \ldots$ (iii)
and $x=0 \ldots$ (i)
Putting the value of x = 0 in eq. (iii), we get
y = 2
Thus, AC and AB intersect at (0, 2)
So, vertices of triangle $\mathrm{ABC}$ are : $(0,1),\left(\frac{1}{2}, 1\right)$ and $(0,2)$
$\therefore$ Area of $\triangle \mathrm{ABC}=\frac{1}{2} \times$ base $\times$ height
$=\frac{1}{2} \times \frac{1}{2} \times 1$
$=\frac{1}{4} \mathrm{sq} .$ units