line symmetry
a line
It will be a line of symmetry creating a 'mirror image'
They occur when you divide something on a line of symmetry.
a hemisphere
I'm assuming you mean "What does dividing into two congruent parts mean?". It means to divide into two identical halves.
a line
The diagonal of a parallelogram divides it into two congruent triangles. This is because the diagonal creates two pairs of congruent triangles by dividing the parallelogram into two equal halves.
congruent halves are just a posh way of saying 'split in two'. but these two shapes must be identical in shape, size, angles, sides etc... they must be exactly the same.
symmetry
A line of symmetry divides a figure into two matching halves.
line of symmetry is divides a figure into halves are the mirror images ofeach other
The diameter of a circle divides it into two halves
line of symmetry is divides a figure into halves are the mirror images ofeach other
It will be a line of symmetry creating a 'mirror image'
Hemispheres
What is axis of symmetry? the axis of symmetry is a line that divides a planar figure into two congurent reflected halves
A bisector is a line or curve which bisects or divides a line segment, angle or other figure into two equal parts.