let’s solve it.
1 2 5
— z - — = —
4 7 7
step 1. simplify both sides of the equation.
1 -2 5
— z + — = —
4 7 7
step 2. add 2/7 to both sides.
1 -2 2 5 2
— z + — + — = — + —
4 7 7 7 7
1
— z = 1
4
step 3. multiply. both sides by 4.
4 * 1
( — z )= (4) * (1)
4
z=4
