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Helppppp!!! 50 pts!

Translate the sentence into an equation.

Three times the sum of a number and 5 is 7.

Use the variable C for the unknown number.

Respuesta :

semsee45

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