Question

triangle ABC congruent triangle DEF by SSS. If AB=(2 rootx-3)cm and DE=(4+rootx)cm, then value of x is

a) 11
b)7
c)49
d) cannot be determined

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Answer 1

Solution :

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∆ABC ≈ ∆ DEF by SSS criteria .

• AB = DE

• BC = EF

• AC = DF

(2√x - 3) = (4+√x)

>> (2√x - √x) = 4+3 = 7

>> √x = 7

>> x = 49

Answer : The value of x is 49. (c) is the correct option.

________________________

Answer 2

Given :-

ABC ≅ DEF by SSS

AB = 2√x - 3

DE = 4 + √x

To Find :-

Value of x

Solution :-

ABC ≅ DEF (SSS)

AB = DE (Sides are equal)

2√x - 3 = 4 + √x

2√x - √x = 4 + 3

√x = 7

On squaring both sides

(√x)² = (7)²

x = 49

Hence,

Value of x is 49