The area of the isosceles triangle formed by the lines 7x−2y+10=0,7x+2y−10=0  and y+2=0  is

Since the slopes of two sides are 72  and −72  they are equally inclined to the x-axis and hence to y+2=0 . The vertex is (0,5) , the coordinates of the ends of the base are (−2,−2)  and (2,−2) . ∴  base =4 and altitude =5+2=7.  ∴  area =12×4×7=14  sq.units.