Respuesta :
Answer:
3(C + 5) = 7
Step-by-step explanation:
Let C = unknown number
The sum of a number and 5:
C + 5
Three times the sum of a number and 5:
3(C + 5)
Three times the sum of a number and 5 is 7:
3(C + 5) = 7
To solve
Use the distributive law: a(b + c) = ab + ac
⇒ 3C + 15 = 7
Subtract 15 from both sides:
⇒ 3C = -8
Divide both sides by 3:
⇒ C = -8/3
- Le the number be c
- Sum of a number and c means c+5
- 3times that means 3(c+5)
So
The expression is
- 3(c+5)=7
On solving
- 3c+15=7
- 3c=-8
- c=-8/3