Working Out Easy Equations does anyone know how to do this equation? I know it's easy but I can't work out what the question means.



When I expanded the first equation:

$(y+4)-(y-3)$

$y^2 -3y +4y - 12$

$y^2-1y-12$

Not sure what I should do after.

Can someone explain how would you work it out in easy terms?

Thank you
When you made the jump from $(y+4)-(y-3)$ to $y^2-3y-4y-12$, you were applying the expansion rules for quantities multiplied together, not subtracted.

multiplication: $(y+4)(y-3)=y^2-3y+4y-12$

Subtraction: $(y+4)-(y-3)=y+4-y+3  = 7$
This is an identity, not an equation. It is true for any real number y. Hence you can't solve the equation to get a single number.