Few True and False questions for geometry.?

1. All right triangles are similar.





2. If two triangles are similar, the ratio of a pair of corresponding angles is equal to the ratio of their perimeters.





3. All rectangles are similar.





4. Two isosceles triangles are similar if the vertex angle of one is congruent to the vertex angle of the other.





true or false please. i need to no them for my test thanks.Few True and False questions for geometry.?
1) False


for a triangle to be similar, all the angles have to be the same.


they will all have a 90degree angle, but depending on the steepness of the hypotenuse, the other two angles may be different.





2) False


the ratio of a pair of corresponding angles would be one, because the triangles are similar, and the ratio of perimeters would not be one, because that would mean they were the same, and they're not, (that would be congruent)





3) False.


For a the shapes to be similar, they also have to have sides that have the same ratio. for example, a square (which is a rectange, by definition) is 4x4. the rectangle is 7x9. they would not have the same ratio. (4/7 does not equal 4/9)





4) True





hope this helps you!