An isosceles triangle has two equal side of length xcm each and a third side of 9cm. If it's perimeter is 24cm what is the van of x?

The perimeter of a isosceles triangle:

P = 2 a + b

where:

a = length of the two equal sides

b = third (unequal) side

P = 2 a + b = 24

In this case a = x , b = 9 cm.

2 x + 9 = 24

Subtract 9 to both sides

2 x + 9 - 9 = 24 - 9

2 x = 15

Divide both sides by 2

x = 7.5 cm

7.5cm

Let's assume that the equal sides of the isosceles triangle have a length of x cm each. The perimeter of the triangle is the sum of the lengths of all three sides.

Perimeter = 2 * equal sides + third side

Given that the perimeter is 24 cm and the third side is 9 cm, we can write the equation as:

24 = 2x + 9

Simplifying the equation:

2x = 24 - 9
2x = 15
x = 7.5

Therefore, the value of x is 7.5 cm.

To find the value of x in this problem, we can use the formula for the perimeter of a triangle, which is the sum of all three sides.

Let's set up the equation using the given information in the problem:

x + x + 9 = 24

Since the two equal sides have a length of x cm each, we can simplify the equation:

2x + 9 = 24

Now, we can solve for x by isolating it on one side of the equation:

2x = 24 - 9
2x = 15

Dividing both sides of the equation by 2 gives us the value of x:

x = 15 / 2
x = 7.5

Therefore, the value of x is 7.5 cm.