Question

Периметр треугольника АВС равен 19,3 см.АС=7,9 см.Сторона АВ в 2 раза короче стороны ВС.Найдите сторону ВС.

Answer 1

Х - АС
2х - ВС

х + 2х + 7,9 = 19,3
3х = 19,3 - 7,9
3х = 11,4 разделим обе части на 3
х = 3,8 - сторона АС
ВС = 2 * 3,8 = 7,6

Answer 2

Perimeter of Triangle ABC

To find the length of side BC in triangle ABC, we can use the given information about the perimeter and the lengths of sides AC and AB.

Let's break down the information given:

- Perimeter of triangle ABC = 19.3 cm - Length of side AC = 7.9 cm - Side AB is twice as short as side BC

To find the length of side BC, we can use the formula for the perimeter of a triangle:

Perimeter (P) = Side AB + Side BC + Side AC

Since side AB is twice as short as side BC, we can represent the length of side AB as 2x, where x is the length of side BC.

Now we can write the equation for the perimeter:

P = 2x + x + 7.9

Simplifying the equation:

19.3 = 3x + 7.9

To solve for x, we need to isolate it on one side of the equation. Subtracting 7.9 from both sides:

19.3 - 7.9 = 3x

11.4 = 3x

Dividing both sides by 3:

x = 11.4 / 3

x = 3.8

Therefore, the length of side BC is 3.8 cm.

Answer:

The length of side BC in triangle ABC is 3.8 cm.