Question

An isosceles triangle has two sides of equal length. The third side is 7 less than twice the length of one of the other sides. If the perimeter of the triangle is 44 cm what is the length of the third side ?

Answer 1

2x+y=44
y+7=2x
y=18.5
x=12.75

Answer 2

Length of the third side is 18.5 cm

Explanation:

An isosceles triangle has two sides of equal length. The third side is 7 less than twice the length of one side of the other side.

Let two equal side of the isosceles triangle = x cm

and third side = y cm

Then y = ( 2x - 7 ) --------(1)

Perimeter of the triangle is 44 cm

then x + x + y = 44

2x + y + 44 -----------(2)

Now we substitute the value of y from equation (1) to equation (2)

2x + ( 2x - 7 ) = 44

4x - 7 = 44

4x = 44 + 7

4x = 51

x =
`(51)/(4)` = 12.75 cm

Now we put x = 12.75 in equation (1)

y = 2(12.75) - 7

= ( 25.5 - 7 )

= ( 18.5 )cm

Therefore, length of third side is ( 18.5 ) cm.