Question

The perimeter of an isosceles triangle is 24cm the length of its congruent side is thirteen less than twice

Answer 1

Step-by-step explanation:

Let the length of the base of the isosceles triangle be x cm and the length of congruent sides be y cm.

Then from the given conditions,

Perimeter of triangle = 24 cm.

∴ x + y + y = 24

∴ x + 2y = 24 ............. eq. no. (1)

According to second condition,

y = 2x – 13

∴ 2x – y = 13 ................. eq. no. (2)

Multiplying equation (2) by 2 we get

4x – 2y = 26 ................. eq. no. (3)

Adding equation (1) and (3)

x + 2y = 24

4x – 2y = 26

5x     =   50

∴ x = 50/5

∴ x = 10

Substituting x = 10 in eq. (1)

x + 2y = 24

∴ 10 + 2y = 24

∴ 2y = 24 – 10

∴ 2y = 14

∴ y = 14/2

∴ y = 7.