G
Guest
Guest
Hello,
I understand you can do anything to one side of an equation as long as you do it to both sides. What I haven't picked up on is "where" you do it to the other side of the equation. For example, let's say you have...
8x + 10 = (3x - 10)/8 (just made that up)
You can remove the 10 from the left side as long as you add -10 to each side. So the left side becomes 8x =, but the right side you have to add -10. I am not sure what the rule is to decide "where" to add -10? I mean, do you remove it from the whole right side, so
8x = ((3x - 10)/8) - 10 ?
Like in this question/answer
Q: b + ax = 12 (solve for X)
A: x = (12 - b) / a
So to arrive at the answer they moved 'b' to the right side by removing it from 12. Makes sense, is the only thing on the right side in the first place. But the second step is to move 'a' to the right side, so they divide "all" of the right side by 'a'. What if when solving you did the solution in the other order, so you went
b + ax = 12
b + x = 12 / a <--- move 'a' to the right side by dividing both sides by it.
x = (12 / a) - b <--- move 'b' to the right side by subtracting it from both sides.
but "x = (12-b)/a" is a very different answer than "x=(12/a)-b"
for example, if x=2, b=2, a=5
the corrent answer figures up like this: 2 = (12-2)/5
my answer figures up like this: 2 = (12 / 5) - 2
which isnt even close to the same thing...
Where am I so confused?
I understand you can do anything to one side of an equation as long as you do it to both sides. What I haven't picked up on is "where" you do it to the other side of the equation. For example, let's say you have...
8x + 10 = (3x - 10)/8 (just made that up)
You can remove the 10 from the left side as long as you add -10 to each side. So the left side becomes 8x =, but the right side you have to add -10. I am not sure what the rule is to decide "where" to add -10? I mean, do you remove it from the whole right side, so
8x = ((3x - 10)/8) - 10 ?
Like in this question/answer
Q: b + ax = 12 (solve for X)
A: x = (12 - b) / a
So to arrive at the answer they moved 'b' to the right side by removing it from 12. Makes sense, is the only thing on the right side in the first place. But the second step is to move 'a' to the right side, so they divide "all" of the right side by 'a'. What if when solving you did the solution in the other order, so you went
b + ax = 12
b + x = 12 / a <--- move 'a' to the right side by dividing both sides by it.
x = (12 / a) - b <--- move 'b' to the right side by subtracting it from both sides.
but "x = (12-b)/a" is a very different answer than "x=(12/a)-b"
for example, if x=2, b=2, a=5
the corrent answer figures up like this: 2 = (12-2)/5
my answer figures up like this: 2 = (12 / 5) - 2
which isnt even close to the same thing...
Where am I so confused?