The perimeter of a triangle is 140 cm the length of the second side is twice the length of the first side the length of the third side is 10 the last than three times the length of the first side

Perimeter = 140

Side 1 = x

Side 2 = 2x

Side 3 = 3x - 10

x + 2x + 3x - 10 = 140

6x - 10 = 140

6x = 150

x = 25

Side 1 = 25 cm

Side 2 = 50 cm

Side 3 = 65 cm

Hope this helps!! :)

the length of the first side is 25 cm.

the length of the second side is 50 cm.

the length of the third side is 65 cm.

Step-by-step explanation:

Let x represent the length of the first side of the triangle.

The length of the second side is twice the length of the first side. It means that the length of the first side is 2x.

the length of the third side is 10 less than three times the length of the first side. It means that the length of the third side is

3x - 10

The formula for determining the perimeter of a triangle is

Perimeter = a + b + c

Where a, b and c are the lengths of each side of the triangle. The perimeter of the triangle is 140 cm. It means that

x + 2x + 3x - 10 = 140

6x = 150

x = 150/6

x = 25

The length of the second side is

25 × 2 = 50 cm

The length of the third side is

25 × 3 - 10 = 65 cm

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4

i would say true? if the unit was informational and it "refreshed your understanding", then true.