In rectangle $ABCD$, $P$ is a point on $BC$ so that $\angle APD=90^{\circ}$. $TS$ is perpendicular to $BC$ with $BP=PT$, as shown. $PD$ intersects $TS$ at $Q$. Point $R$ is on $CD$ such that $RA$ passes through $Q$. In $\triangle PQA$, $PA=20$, $AQ=25$ and $QP=15$. Find $SD$. (Express your answer as a common fraction.)

In rectangle ABCD P is a point on BC so that angle APD90circ TS is perpendicular to BC with BPPT as shown PD intersects TS at Q Point R is on CD such that RA pa class=

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Answer:

28/3

Step-by-step explanation:

AB = 16

AP = 20

Triangle ABP is a right triangle.

(AB)^2 + (BP)^2 = (AP)^2

16^2 + (BP)^2 = 20^2

BP^2 = 144

BP = 12

BP = PT = 12

AS = BP + PT = 12 + 12 = 24

Triangle AQS is a right triangle.

(AS)^2 + (SQ)^2 = (AQ)^2

AQ = 25

24^2 + (SQ)^2 = 25^2

SQ = 7

Triangle PQT is a right triangle.

(PT)^2 + (QT)^2 = (PQ)^2

12^2 + (QT)^2 = 15^2

QT = 9

Triangle PTQ is similar to triangle DSQ.

PT/QT = SD/SQ

12/9 = SD/7

9SD = 12 * 7

SD = (12 * 7)/9

SD = 28/3

Answer:

[tex]\frac{28}{3}[/tex]

Step-by-step explanation:

Given information: ABCD is a rectangle, [tex]\angle APD=90^{\circ}[/tex], PA=20, AQ=25 and QP=15.

In a right angled triangle

[tex]hypotenuse^2=base^2+perpendicular^2[/tex]

In triangle ABP, AB = 16 and AP = 20. Using Pythagoras theorem we get

[tex](AB)^2 + (BP)^2 = (AP)^2[/tex]

[tex]16^2 + (BP)^2 = 20^2[/tex]

[tex](BP)^2 = 20^2-16^2[/tex]

[tex]BP^2 = 144[/tex]

[tex]BP = 12[/tex]

Since BP = PT, therefore PT = 12.

[tex]AS = BP + PT = 12 + 12 = 24[/tex]

AQS is a right angled triangle and AQ = 25. Use Pythagoras theorem in triangle AQS.

[tex](AS)^2 + (SQ)^2 = (AQ)^2[/tex]

[tex]24^2 + (SQ)^2 = 25^2[/tex]

[tex]SQ = 7[/tex]

Triangle PQT is a right triangle. Use Pythagoras theorem in triangle PQT.

[tex](PT)^2 + (QT)^2 = (PQ)^2[/tex]

[tex]12^2 + (QT)^2 = 15^2[/tex]

[tex]QT = 9[/tex]

In triangle  PTQ and DSQ,

[tex]\angle TQP=\angle SQD[/tex]             (Vertical angles)

[tex]\angle PTQ=\angle DSQ[/tex]             (Right angles)

Triangle PTQ is similar to triangle DSQ by AA property of similarity.

Corresponding parts of similar triangles are proportional.

[tex]\frac{PT}{QT}=\frac{SD}{SQ}[/tex]

[tex]\frac{12}{9}=\frac{SD}{7}[/tex]

On cross multiplication we get

[tex]9SD=12\times 7[/tex]

[tex]9SD=84[/tex]

Divide both sides by 9.

[tex]SD=\frac{84}{9}[/tex]

[tex]SD=\frac{28}{3}[/tex]

Therefore, [tex]SD=\frac{28}{3}[/tex].

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