Make an equation and find the sides if the perimeter of triangle ABC is 68 cm AB is equal

| August 17, 2021 | education

Make an equation and find the sides if the perimeter of triangle ABC is 68 cm AB is equal to x cm BC is 2 times AB and AC is 7 cm less than BC.

The problem statement already contains x – this is the length of the side AB. Then the length of the side BC is 2x cm, and the length of AC is (2x – 7) cm.The perimeter of the triangle ABC is:

P = AB + BC + AC.

Hence, according to the conditions of the problem, the following equation can be drawn up:

x + 2x + (2x – 7) = 68.

Let’s solve it:

x + 2x + (2x – 7) = 68,

x + 2x + 2x – 7 = 68,

5x = 68 + 7,

5x = 75,

x = 75/5,

x = 15 cm.

We found the AB side. Next, we find the length of the side BC:

BC = 2 * 15 = 30 cm.

Now let’s find AC:

AC = 30 – 7 = 23 cm.

Answer: the sides of triangle ABC are equal: AB = 15 cm, BC = 30 cm and AC = 23 cm.



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