### Solution

a

$a+b=4⇔b=4−a$

b

To isolate $b$ we have to add $d$ on both sides of the equation. $b−d=t⇔b=t+d$

c

In this equation we have $5b$ on the left-hand side. Thus, we can divide both sides by $5$ in order to solve for $b.$ $5b=q⇔b=5q $

d

To solve for $b$ we can multiply both sides by $y.$ $yb =s⇔b=sy$

### Hint

a

To solve the equations for $b$ we can use inverse operations to move the other variables.

b

To solve the equations for $b$ we can use inverse operations to move the other variables.

c

To solve the equations for $b$ we can use inverse operations to move the other variables.

d

To solve the equations for $b$ we can use inverse operations to move the other variables.

### Answer

a

$b=4−a$

b

$b=t+d$

c

$b=5q $

d

$b=sy$