Question

Looking for geometry proof help on a problem with parallelograms and an isosceles triangle

Answer 1

Explanation:

30. Given: rectangles QRST and RKST

Prove: ΔQSK is isosceles

An isosceles triangle is a triangle which has two sides and two angles to be equal.

Thus,

From rectangle QRST, the diagonals of rectangles are similar.

i.e RT ≅ QS (diagonal property)

Also, RT ≅ SK (opposite sides of rectangle RKST)

Thus,

RT ≅ QS ≅ SK

Therefore,

ΔQSK is an isosceles triangle.

31. Given: Rectangles QRST, RKST and JQST

Prove: JT ≅ KS

From rectangle QRST, the diagonals of rectangles are similar.

i.e RT ≅ QS (diagonal property)

But,

JT // QS and RT // KS

Thus,

JT ≅ QS (opposite sides of rectangle JQST)

also,

RT ≅ KS (opposite sides of rectangle RKST)

So that,

JT ≅ QS ≅ RT ≅ KS

Therefore,

JT ≅ KS