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# a drinking straw of length 21cm is cut into 3 pieces.the length of the first piece is x cm the second piece is 3cm shorter than the first piece.

A drinking straw of length  21 Cm is cut into 3 pieces.the length of the first piece is x cm the second piece is 3cm shorter than the first piece.

(a)state,in terms of x,the length of  each of the piece.
(b)write an expression,in terms of x, to represent the sum of the lengths of the three pieces of drinking straw.
(c)hence,calculate the value of x

### 1 Answer by Expert Tutors

Vivian L. | Microsoft Word/Excel/Outlook, essay composition, math; I LOVE TO TEACHMicrosoft Word/Excel/Outlook, essay comp...
3.0 3.0 (1 lesson ratings) (1)
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Hi again Shelcia;
FIRST PIECE...x cm
SECOND PIECE...(x-3) cm
THIRD PIECE...no information
I am going to assume that the THIRD PIECE is twice the length of the FIRST.
THIRD PIECE...(2x) cm

21=x+(x-3)+(2x)
21=x+x-3+2x
21=4x-3
Let's add 3 to both sides as we proceed to isolate x...
21+3=4x-3+3
24=4x
Let's divide both sides by 4...
24/4=(4x)/4
6=x

FIRST PIECE...6 cm
SECOND PIECE...(6-3) cm=3 cm
THIRD PIECE????2(6)cm=12 cm

(6+3+12) cm=21 cm