When you reverse the digits in a certain two digit number you decrease it’s value by 36. find the number if the sum of its digits is 10

The number is 73.

Step-by-step explanation:

I. 10b + a = 10a + b - 36

II. a + b = 10 --> b = 10 - a

II in I

10b + a = 10a + b - 36

9b = 9a - 36

9(10 - a) = 9a - 36

90 - 9a = 9a - 36

126 = 18a

a = 7

b = 10 - 7 = 3

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

option (b) is correct

step-by-step explanation:

to find the solution of this system, we need to convert it into reduced row-echelon form. we have,

after applying row operations r2 -> r2/2 and r3 -> r3/3, we get,