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You can use slope to measure the diagonals. If the product of their slopes is -1 then they are perpendicular.

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Draw a square. Note the coordinates for the corners. For instance, my corners are (0,0), (1,0), (1,1), and (0,1). Consider each diagonal (0,0)-(1,1) and (1,0)-(0,1)

Recall that the slope of a line is delta y over delta x. The slope of the first diagonal is 1, while the slope of the second diagonal is -1. 1 times -1 is -1, which means that the diagonals are perpendicular.

Note: This works for any square, except where one of the diagonals has infinite slope, i.e. a vertical line. In that case, you can simply state that one diagonal has infinite slope and the other diagonal has zero slope. The math does not work, because this proof is based on Cartesian coordinates. You can make it work by converting to polar coordinates and comparing the two thetas. They should have a relationship where the absolute value of theta 1 minus theta 2 is equal to pi.

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Q: How do you prove that the diagonals of a square are perpendicular to each other?
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Why are the diagonals of a square perpendicular bisectors of each other?

You could prove this by congruent triangles, but here are two simpler arguments: --------------- Since a square is a rhombus, and the diagonals of a rhombus are perpendicular bisectors of each other, then the diagonals of a square must be perpendicular bisectors of each other -------------------- A square has four-fold rotational symmetry - as you rotate it around the point where the diagonals cross, there are four positions in which it looks the same. This means that the four angles at the centre must be equal. They will each measure 360/4 = 90 degrees, so the diagonals are perpendicular. Also. the four segments joining the centre to a vertex are all equal, so the diagonals bisect each other.


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prove any two adjacent triangles as congruent


How do you prove that the diagonals of a square are equal and bisect each other at right angles?

it would produce two right angle triangleImproved Answer:-Measure them and use a protractor which will result in equal measures of 4 by 90 degrees angles


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How do you prove the diagonals of an isosceles triangle congruent?

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Show that if diagonals of a quadrilateral bisects each other then it is a rhombus?

This cannot be proven, because it is not generally true. If the diagonals of a quadrilateral bisect each other, then it is a parallelogram. And conversely, the diagonals of any parallelogram bisect each other. However not every parallelogram is a rhombus.However, if the diagonals are perpendicular bisectors, then we have a rhombus.Consider quadrilateral ABCD, with diagonals intersecting at X, whereAC and BD are perpendicular;AX=XC;BX=XD.Then angles AXB, BXC, CXD, DXA are all right angles and are congruent.By the ASA theorem, triangles AXB, BXC, CXD and DXA are all congruent.This means that AB=BC=CD=DA.Since the sides of the quadrilateral ABCD are congruent, it is a rhombus.


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