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# Using Properties of Proportion Solve for X (Sqrt(X + 5) + Sqrt(X - 16))/(Sqrt(X + 5) - Sqrt(X - 16)) = 7/3 - ICSE Class 10 - Mathematics

#### Question

Using properties of proportion solve for x

(sqrt(x + 5) + sqrt(x - 16))/(sqrt(x + 5) - sqrt(x - 16)) = 7/3

#### Solution

(sqrt(x + 5) + sqrt(x - 16))/(sqrt(x + 5) - sqrt(x - 16)) = 7/3

Applying componendo and dividendo

(sqrt(x + 5)+ sqrt(x - 16) + sqrt(x + 5) - sqrt(x - 16))/(sqrt(x + 5)+sqrt(x - 16) - sqrt(x + 5) + sqrt(x -16)) = (7 + 3)/(7 - 3)

(2sqrt(x + 5))/(2sqrt(x - 16)) = 10/4

sqrt(x + 5)/sqrt(x - 16) = 5/2

Squaring both sides

(x + 5)/(x - 16) = 25/4

4x + 20 = 25x - 400

21x = 420

x = 420/21 = 20

Is there an error in this question or solution?

#### APPEARS IN

Selina Solution for Selina ICSE Concise Mathematics for Class 10 (2018-2019) (2017 to Current)
Chapter 7: Ratio and Proportion (Including Properties and Uses)
Ex.7C | Q: 11.1

#### Video TutorialsVIEW ALL [1]

Solution Using Properties of Proportion Solve for X (Sqrt(X + 5) + Sqrt(X - 16))/(Sqrt(X + 5) - Sqrt(X - 16)) = 7/3 Concept: Proportions.
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