Question

The Third Side Is Called The base if an isosceles triangle has perimeter 345 cm and base length 85 cm what is the length of each leg

Answer 1

The length of each leg of the isosceles triangle is 130 cm.

Explanation:

Base of the isosceles triangle: B=85 cm

Length of each leg: L=?

Perimeter: P=345 cm

P=B+L+L

P=B+2L

Replacing P by 345 cm and B by 85 cm in the equation above:

345 cm = 85 cm + 2L

Solving for L: Subtracting 85 cm both sides in the equation above:

345 cm - 85 cm = 85 cm +2L - 85 cm

260 cm = 2L

Dividing by 2 both sides in the equation above:

260 cm / 2 = 2L/2

130 cm = L

L = 130 cm

Answer 2

Length of each leg = 130 cm.

Explanation:

Given that there is an isosceles triangle which has perimeter 345 cm.

Base length =85 cm.

Since other two sides are equal, let the equal size = x

Perimeter = sum of all 3 sides of a triangle

= 85+x+x = 85+2x

But perimeter = 345 (given)

So equate x term perimeter with actual

85+2x = 345

Subtract 85

2x = 260

Divide by 2

x =130 cm.

Hence answer is 130 cm.