Need help with some math
So I got a bunch of word problems for hw and i have no idea how to do some of them. Can you guys help me?
1st question: The sum of two numbers is 125. Five times one number minus three times the other is 41 determine the number.
2nd question: Hannah is 7 years younger than Attila. If Hannah's age is multiplied by 5, it is 49 more than double Attila's age. What is Hannah's age?
I need help because I don't know how to make the equation =/ (using 1variable)
April 22, 2011
3 Comments • Newest first
My brain isn't working right now, I was just confused why he had multiplied the top equation by 3 but I later realized it was to cancel out the second variable :S
I'm an idiot, I didn't get enough sleep last night so I wasn't paying attention in math class -_-
I still don't understand, could you explain again?
EDIT:Nvm I understand now! Ty so much!
Why do you feel the need to use only one variable?
Question 1:
Let the first number be x, the second number be y.
x+y = 125
5x - 3y = 41
Multiply the first equation throughout by 3 to get 3x + 3y = 375
Add the equations together:
3x + 3y = 375
5x - 3y = 41
____________+
8x = 416
x = 52
y = 73
Question 2:
Let Hannah's age be x, Attila's age be y.
x = y - 7
5x = 2y + 49
Same deal, I'm sure you can work it out.