Respuesta :
Answer:
10.5
Step-by-step explanation:
common denominator for 7z and 3z is 21z
4/7z = 12/21z
2/3z = 14/21z
12/21z + 14/21z = 13
26/21z = 13
cross-multiply to get:
26z = 273
z = 273/26
z = 10.5
Answer:
z = 10.5
Step-by-step explanation:
(4/7)z + (2/3)z = 13
multiply by 21 to eliminate the fractions
12z + 14z = 273
26z = 273
Divide both sides by 26
z = 10.5