c今年40歲,剛好isD歲數的2倍少8歲。D今年幾歲?

D=24

D的2倍=48

D的2倍少8歲=48-8

c=40

所以D=24

Let y be the age of D.
40=2y-8
48=2y
y=48/2
y=24
Therefore, D is 24 years old.

REFERS TO THE QUESTION : C = 40 = 2D - 8
40 = 2D - 8
48 = 2D
24 = D
所以 D IS 24 歲

設D現在x歲。
2x-8=40
2x=40+8
2x=48
x=48/2
x=24
所以D現在24歲。

2D-8=40

2D-8+8=40+8

2D/2=48/2

D=24

2D-8=40
2D=48
D=24
so D is 24 years old

c今年40歲,剛好isD歲數的2倍少8歲。D今年幾歲?

2x-8=40

2x=48

x=24

.'.D今年24歲

啦，c今年40歲 C=40 (1)
這樣c is d 2倍少8歲 C=2D-8 (2)
將(2) 入 (1) 40=2D-8
48=2D
D=24歲

因為C = 40
C = 2D - 8
40 = 2D - 8
2D = 48
D = 24
D今年24歲