URGENT- A rectangle has an area of 210 cm 2 and a perimeter of 58 cm. What are its dimensions? (show work)

L= 29-b

Step-by-step explanation:

A=210cm^2

A= L*b

210= (29-b) b

210= 29b-b^2

b^2-29b+210=0

b^2-15b-14b+210=0

b(b-15)-14(b-15)=0

(b-15)(b-14)=0

R=14 B=15

P-58cm

p=2(l+b)

58=2(l+b)

29= l+b

L= 29-b

56.6

step-by-step explanation:

the ratio of the perimeters is equal to the scale.

the ratio of the areas is equal to the square of the scale.

34 / 20 = k

a / 19.6 = k²

substituting:

a / 19.6 = (34 / 20)²

a = 19.6 (34 / 20)²

a ≈ 56.6

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m