A wire with a length of 100 cm is cut into three parts. The length of wire of the first and second parts are the same. The length of the third part of the wire exceeds the sum of the first two parts by 4 cm. Calculate the length of each part.

The first two pieces are the same, let each of those equal x, so you have x + x = 2x

The 3rd piece is the sum of the first two + 4, so this would be 2x + 4

Now you have 2x + 2x + 4 = 100 cm

Combine like terms:

4x +4 = 100

Subtract 4 from both sides

4x = 96

Divide both sides by 4

X = 24

First piece is 24 cm

Second piece is 24 cm

Third piece is 52 cm

hello from mrbilldoesmath!

answer:

25x^2 + 90x + 84

discussion:

mn(x) = m(n(x)) = m( 5x + 9) =

(5x + 9)^2 + 3 =>

25x^2 + 90x + 9^2 + 3 =

25x^2 + 90x + 84                 (as 9^2 = 9*9 = 81)

which is the second choice

regards,  

mrb

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step-by-step explanation: