If a-b/b=3/7 which of the follow must also be true
A) a/b = -4/7
B) a/b = 10/7
C) a+b/b=10/7
Why it’s choice b
It supposed choice c
The problem does not appear to be stated correctly.
It looks like it should read: (a-b)/b=3/7
To solve:
(a/b)-(b/b)=3/7
or (a/b)-1=3/7
or a/b=10/7
B is the correct answer.
or alternatively:
(a-b)/b = 3/7
cross multiply and:
7(a-b) = 3b
expand
7a-7b = 3b
simplify
7a-10b = 0
then you can see that:
7a = 10b
which if you divide both sides by 7 then by b:
a/b = 10/7
sorry if this is overcomplicating the question— apparently i overcomplicate questions, but i understand it this way, so hopefully the same goes for you 
That’s the thing about math, there is typically more than one way to solve a problem. Whatever way works the best for you is the way to go.
The flip side to the statement above is that one should never learn to solve math problems by learning a bunch of steps. You will never be able to cram all those steps and the exact circumstances where they can be used into one’s brain. Math is a visual / spatial skill. You actually learn to visualize the process for finding the answer. However, it is taught many times as a series of steps without having the student learn why. I believe that this is the reason so many people have problems with math. It isn’t taught correctly.
And the brute force way - the denominators are b and 7, so set b=7. What does a need to be to make the denominator 3? a=10. Then plug them into the possible answers. It’s always good the have the brute force/trial and error method in your pocket if you can’t algebraically solve.
The answer is B)
^^ Why does B always become the emoij??
It’s the B and ) together B)