How do you solve for a in $ab + c = d$ ?

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Answer 1 · 2016-07-07T19:54:48

$a = (d-c)/b$

Remember we can do pretty much anything we like to an equation as long as we do the same to both sides.

Subtract $c$ from both sides:

$ab + c color(red)(-c) = d color(red)(-c)$

$therefore ab = d - c$

Divide both sides by $b$

$(ab)/(color(red)(b)) = (d-c)/(color(red)(b))$

$therefore a = (d-c)/b$

How do you solve for a in ab + c = dab + c = d?