Question:
Right. well here's the question:
The sum of 2 numbers is 39. Twice the first number plus 3 times the second number is 101. Find the numbers.
So, I think I have to write an equation to figure this out but, I'm really confused on how to. Right now, we only know how to solve for one variable questions though,
ex. 2x-3x+4=2x+1
Only one variable like x in one equation. So, is there a way of doing this questions with using one variable?
THANKKKKKKS, if you could help 3
Answer:
this problem doesnt make sense to me.
Answer:
i don't think you can do it without using two variables can you?
x+y=39
2x+3y=101
and you solve for a variable and plug it in, and plug in the next number you get
Answer:
^Yeah that's what I thought
But I dont think in grade nine, or yet we have learned to even solve for two variables. So I wouldn't know how. But I just didn't think they'd give us a question on something we haven't even learned about (IMG:style_emoticons/default/blink.gif)
Answer:
the first equation is x+y=39, second equation is 2x+3y=101
use elimination to eliminate one of the variables, that way u will get the value for either y or x
say you found the value for y, so you substitute y into the any of the equations to get the value for x
and there you go! =D
Answer:
16 and 23
Hmm, as for the equation... Let's see....no idea.
I was thinking the same thing as ddragon/ana though....
Answer:
isn't it basically algebra?
like 1st number = a
2nd number = b
a+b=39
2a+3b=101
but that would semi work if it was only one variable..
Answer:
anna_85 - haha (IMG:style_emoticons/default/sweatingbullets.gif) except i don't know how to fine the value of either y or x but thanks =]
Answer:
^ lol
heres how you do it...
subtract both equations:
2 (x+y=39) --> multiple by 2 so u can eliminate x
2x+3y = 101
you'll get y=23
sub y into x+y=39 and u'll get x
Answer:
Hahaha this is so random because I really should be doing my economic assignment -.- LOL but yeah
1) x+y=39
2) 2x+3y=101
change equation 1 into y=39-x by moving the x to the right hand side
replace y=39-x into the 2nd equation 2x+3(39-x)=101
solve for x to get 16
plug 16 back into the first equation 16+y=39
y=39-16 y=23
Hope that helped haha lOL so yeah... x=16 & y=23 ^^
Answer:
OMGGG
I I FOUND OUT HOW TO DO IT WITH ONE VARIBLE
.
Let x= the first number
39-x= the second number
So the equation would be 2x+3(39-x)= 101
Answer:
To do it with one variable:
The first number would be x. The second number would be 39 - x, because when you figure out the first number, the second should be easy to figure out.
Now we start giving them the value. It says two times the first number, so that becomes 2x. Then to that, you add three times the second number, so that would be 3 (39 - x). Both of those has to add up to 101.
So in short, it would be 2x + 3(39-x) = 101
Answer:
Hahaha this is so random because I really should be doing my economic assignment -.- LOL but yeah
1) x+y=39
2) 2x+3y=101
change equation 1 into y=39-x by moving the x to the right hand side
replace y=39-x into the 2nd equation 2x+3(39-x)=101
solve for x to get 16
plug 16 back into the first equation 16+y=39
y=39-16 y=23
Hope that helped haha lOL so yeah... x=16 & y=23 ^^
LMAO
thank you.
I just figured it out.
But wow thanks!
Thanks alot guys 3
haha I really appreciate it.
I was stuck on that question for god knows how long.
Answer:
it's just substitution, don't worry, with more practice you'll get the hang of it
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hahahahhaaha
i feel stupid now (IMG:style_emoticons/default/sad.gif)
Answer:
waittt....aren't you supposed to eliminate and then substitute for the answer that you got. so likeeee. its like this.
x+y=39
2x+3y=101
right??
and then.....
-2(x+y)=39.......and you'll end up withhhh.......
-2x-2y=-78...........and RIGHT ON THE BOTTOM OF IT you have to eliminate numbers so in this case eliminate the x's
2x+3y=101
y=23.............basic math heree........
x+23=39................substitution
x=16..............subtract 23 on both sides.....
and BAMMMM!!!!
y=23, x=16..........YOUR ANSWERSSSSSS!!!! hahaha. hope i'm rightttt....
Answer:
whoot.. you finally figured it out..
Answer:
whoot.. you finally figured it out..
omgggg I WAS RIGHT!??!!?!? MEEE?!?!!? YAYY!!!! WOOT WOOOOOOOTTTTTT!!!!! YEAHHHHH BOIIIII!!!
Answer:
Closing, question answered already.
