I need help, The question is 7x + 2x -4y thanks if you helped.

When a formula is solved for a particular variable, several different equivalent forms may be possible. if we solved a=1/2bh for h, one possible correct answer is h=2a/b . which one of the following is not equivalent to this? a. h= 2(a/b) b. h= 2a(1/b) c. h= a/1/2b d. h= 1/2a/b

I'm confused on this could anyone me and show me what i need to do to solve it.

Rose bought a new hat when she was on vacation. the following formula describes the percent sales tax rose paid b=t-c/c