Is it possible to express a+b in terms of x and y if:
2a+b = x (1)
b-a = y (2)
These were some of my failures:
b = y-a
Substitute b into 1
2a + y-a = x
a + y = x
a = x-y
and then from there I tried
a + b = x - y + b (But this definitely looks wrong)
a + b = x - y + (y - a)
then I tried
2a = x - b
a = (x - b)/2
b = y - a
a + b = (x - b)/2 + y - a
a + b = (x - b)/2 + (2y - 2a)/2
a + b = [(x - b) + (2y - 2a)]/2
a + b =[2x + x - 2a - b]/2---------> I can't seem to remove a and b from this side of the equality
and then it keeps going on and I don't even know if what I'm doing is actually right within the rules of mathematics.
One of my efforts seemed to go down the right direction towards getting an answer, but I noticed that I accidentally did something wrong...
b-a = y
a = y+b (Which is definitely wrong but I didn't notice at the time)
a = (x - b)/2
y+b = (x-b)/2
2y + 2b = (x-b)
2y - x = -3b
b = (-2y+x)/3 ------->I use this below
and then for some reason I took the equation:
a = y + b
a + b = y + 2b
a + b = y + 2[(-2y+x)/3]
a + b = y + (-4y+2x)/3
a + b = (3y + -4y + 2x)/3
a + b = (2x-y)/3
The answer is supposed to be (2x+y)/3
Could someone help nudge me in the right direction?
(I had no idea where to post this question, so I decided to post it here... if I should've posted it somewhere else, I'll move this post to that category)
2a+b = x (1)
b-a = y (2)
These were some of my failures:
b = y-a
Substitute b into 1
2a + y-a = x
a + y = x
a = x-y
and then from there I tried
a + b = x - y + b (But this definitely looks wrong)
a + b = x - y + (y - a)
then I tried
2a = x - b
a = (x - b)/2
b = y - a
a + b = (x - b)/2 + y - a
a + b = (x - b)/2 + (2y - 2a)/2
a + b = [(x - b) + (2y - 2a)]/2
a + b =[2x + x - 2a - b]/2---------> I can't seem to remove a and b from this side of the equality
and then it keeps going on and I don't even know if what I'm doing is actually right within the rules of mathematics.
One of my efforts seemed to go down the right direction towards getting an answer, but I noticed that I accidentally did something wrong...
b-a = y
a = y+b (Which is definitely wrong but I didn't notice at the time)
a = (x - b)/2
y+b = (x-b)/2
2y + 2b = (x-b)
2y - x = -3b
b = (-2y+x)/3 ------->I use this below
and then for some reason I took the equation:
a = y + b
a + b = y + 2b
a + b = y + 2[(-2y+x)/3]
a + b = y + (-4y+2x)/3
a + b = (3y + -4y + 2x)/3
a + b = (2x-y)/3
The answer is supposed to be (2x+y)/3
Could someone help nudge me in the right direction?
(I had no idea where to post this question, so I decided to post it here... if I should've posted it somewhere else, I'll move this post to that category)
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