sofia4696
sofia4696 sofia4696
  • 12-02-2021
  • Mathematics
contestada

Solve the system by substitution.
3x + y = 20
-7y=x

Please help

Respuesta :

sqdancefan
sqdancefan sqdancefan
  • 13-02-2021

9514 1404 393

Answer:

  (x, y) = (7, -1)

Step-by-step explanation:

The expression for x makes it easy to use that for substitution.

  3(-7y) +y = 20

  -20y = 20 . . . . . collect terms

  y = -1 . . . . . . . . . divide by -20

  -7(-1) = x = 7 . . . use y in the second equation to find x

The solution is (x, y) = (7, -1).

Answer Link

Otras preguntas

I need help with finding the answer of 21 laps in 7 minutes
Take a look at the statement below: Fish meal is better than artificial fertilizers. How could this statement be revised to make it a hypothesis?
If an orange is orange, why isn't a lime called a green or a lemon called a yellow?
6 cakes cost to pound £2.40 how much does 10 cakes cost?
why do we need both a small and large intestine?
what should an operator do when attempting to re-board a personal watercraft (PWC)?
Imagine you are a historian reflecting on this period in history. You've been asked to create a product that describes the Spanish American War or the building
wendy's brother drank 3/10 of the gallon of milk in the fridge. what percent of the milk did he drink.
1. Name two elements that go through alpha decay
The planet we call earth has how many layers