No but it does have a perpendicular line of symmetry.
None but its apex is perpendicular to its base
No but it does have 3 sides 2 of which are of equal lengths.
No
Only one line of symmetry, it is the line that contains the median of the isosceles triangle (that passes through the vertex and perpendicular to the base).
There can be only one pair of perpendicular lines in an isosceles triangle when it is a right angled isosceles triangle. A non right angled isosceles triangle has no pairs of perpendicular lines.
No but it does have a perpendicular line of symmetry.
If it is a 45° 45° 90° isosceles right triangle, then there are 2 sides that are perpendicular.
None but its apex is perpendicular to its base
No but it does have 3 sides 2 of which are of equal lengths.
The isosceles triangle has one line of symmetry, the perpendicular bisector of the base
No
Only one line of symmetry, it is the line that contains the median of the isosceles triangle (that passes through the vertex and perpendicular to the base).
The only requirement for an isosceles triangle is that two sides be the same length and one be different. It is possible for an isosceles triangle to have two perpendicular legs. It would be right and isosceles.
An isosceles right triangle is a 45° 45° 90° triangle. If you know how to construct a right angle (two lines that are perpendicular), then just take a compass, with the point on the intersection of the perpendicular lines, and mark the same distance on each of the perpendicular lines, then use a straight edge to connect those two points. Or, if you have a square, you can connect two of opposite corners with a diagonal and you will have 2 triangles, both of them isosceles right triangles.
The altitude line is perpendicular to the base and bisects the apex of the isosceles triangle.
The perpendicular bisectors only intersect on the triangle when it is an isosceles right triangle.