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Does anyone know how to do this one or how to set it up to solve? I’ve tried a few different things but I’m not sure if they were right.

Does anyone know how to do this one or how to set it up to solve? I’ve tried a few-example-1

1 Answer

1 vote

The value of QT in the figure is 45

How to determine proportional sides in similar triangles

From the figure

Given that ∆STR is similar to ∆PTQ,

For similar triangles their corresponding sides are proportional.

Therefore,

PT/ST = QT/RT

PT = ST - SP

= 65 - 26 = 39

QT = 4x -3, RT = 4x - 3 + 30

RT = 4x + 27

Let's find x

39/65 = 4x - 3/4x + 27

39(4x + 27) = 65(4x - 3)

Expand and simplify both sides of the equation:

156x + 1053 = 260x - 195

1053 + 195 = 260x - 156x

Combine like terms:

1248 = 104x

x = 1248/104

Simplify the fraction:

x = 12

Therefore, the solution to the equation is x = 12

QT = 4x - 3

= 4(12) -3

= 48 - 3 = 45

The value of QT is 45

User Belal
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