7th grade math
posted by Abby on .
Horses, pigs and cows is really easy I can do it in my head but, my teacher told me I would have to start showing my work. I really have no clue how to do that I have always done it in my head. Can you pretty please help me I would gladly appreciate it. Thank you. :)
I don't know what's in your head!!
What is the problem?
My teacher gave me an example (I don't know so sorry)
12 = h
Thanks (it's really confusing)
Please post a problem that you did in your head, and I'll try to help you.
(Blank) horses + (blank) pigs =22
(Blank) horses + (blank) cows =9
(Blank) pigs + (blank) cows =17
Hope that gives you an idea of what I am talking 'bout (if I could take a pic. I would)
Sorry I meant 22
Are you working with variables?
let the number of horses be x
let the number of pigs be y
let the number of cows be z
so you have:
x+y = 22 #1
x+z = 9 #2
y+z = 17 #3
subtract #1 - #2 ----> y-z = 13 #4
add #3+#4 ----> 2y = 30
y = 15
sub into #1
sub into #2
x+z = 9
7+z = 9
z = 2
we have 7 horses, 15 pigs, and 2 cows
Thanks Reiny :) (sorry its all ratchit and says lexie b/c my 'lil sis was putting a ? And 4got 2 put it back to Abby)