Question

How do you solve `-5/4a + 1 + 5/2a = 21/16`?

Answer 1

`a = 9/5`

Explanation:

`-5/4a + 1 + 5/2a = 21/16" get rid of the denominators"`

`(-5acolor(blue)(xx16))/4 + 1color(blue)(xx16) + (5acolor(blue)(xx16))/2 = (21color(blue)(xx16))/16" "LCM = color(blue)(16)`

`(-5acolor(blue)(xxcancel16^4))/cancel4 + 1color(blue)(xx16) + (5acolor(blue)(xxcancel16^8))/cancel2 = (21color(blue)(xxcancel16))/cancel16`

`-20a + 16 +40a = 21`

`20a = 36`

`a = 36/20 = 9/5`