Question

27. Two equal sides of a triangle are (x + 6) cm and (5x - 2) cm. If the third side
(7x - 4) cm, find x. Then, find the perimeter of the triangle.
(5
15. Find the anglesa​

Answer 1

Step-by-step explanation:

just add it and take them equal to 180

Answer 2

Required Solution :

Given:

• Two equal sides of a triangle are (x + 6) cm and (5x - 2) cm.

• Third side = (7x - 4) cm.

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To calculate:

• Value of x.

• Perimeter of triangle

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Calculation:

→ Value of x.

As the question states that,

• (x + 6) cm and (5x - 2) cm are two equal sides of a ∆, then

⇒ x + 6 = 5x - 2

• Step 1 : Transposing the like terms.

⇒ 6 + 2 = 5x - x

• Step 2 : Performing addition and substraction.

⇒ 8 = 4x

• Step 3 : Transposing 4 from RHS to LHS.

⇒ $\dfrac{8}{4}$ = x

• Step 4 : Performing division.

⇒ 2 = x

Therefore, value of x is 2 cm.

→ Perimeter of ∆ :

We know that,

→ Perimeter of ∆ = Sum of all sides

As we are given the sides of the triangle, then inserting the values in the formula :

⇒ Perimeter of ∆ = ( x + 6 ) + ( 5x - 2 ) + ( 7x - 4 )

• Step 1 : Removing brackets

⇒ Perimeter of ∆ = x + 6 + 5x - 2 + 7x - 4

• Step 2 : Collecting all the like terms

⇒ Perimeter of ∆ = x + 5x + 7x + 6 - 2 - 4

• Step 3 : Performing addition and substraction

⇒ Perimeter of ∆ = 13x + 0

• Step 4 : Again performing addition.

⇒ Perimeter of ∆ = 13x

• Step 5 : Substituting the value of x.

⇒ Perimeter of ∆ = 13 × 2

• Step 6 : Performing multiplication

⇒ Perimeter of ∆ = 26 cm.

Therefore, perimeter of the ∆ is 26 cm.