Question

Momi is working two jobs. One, as a dog walker, pays $12 an hour. The other is doing office work for $9 an hour. She works a total of 15 hours a week and she receives $162 a week. Write two equations, and solve them to find out how many hours she works each job. You need to show the definition of your variables

Answer 1

Let 'x' be the number of hours she wors as a dog walker
Payment she receives = 12x $ / hour
Let 'y' be the number of hours she does office work
Payment she received = 9y $/hour

Total number of hours she works constraint : x+y = 15 hours / week;
Total payment she receives = 12x + 9y = 162 $ / week
We know that:

x+y = 15;
12x + 9y = 162
3x + 9x + 9y = 162
3x + 9 (x+y) = 162
3x + 9 (15) = 162
3x + 135 = 162
3x = 162 - 135
3x = 27;
x=9

if x = 9 then y = 15 - x = 15 - 9 = 6

Thus, she works as a dog walker for 9 hours a week and does office work for 6 hours a week;