PLEASE HELP ME WITH THESE QUESTIONS!!

1. What is the solution of the system?

4xβˆ’y=βˆ’38
x+y=3


2. What is the solution of the system?

βˆ’3x+9y=36
4x+12y=24


3. What is the solution of the system of equations?

7/2xβˆ’1/2y=9/2
3xβˆ’y=5

Respuesta :

Answer:

3. [1, βˆ’2]

2. [βˆ’3, 3]

1. [βˆ’7, 10]

Step-by-step explanation:

3.

{7⁄2x - Β½y = 9⁄2

{3x - y = 5

-6⁄7[7⁄2x - Β½y = 9⁄2]

{βˆ’3x + 3⁄7y = βˆ’3 6⁄7 >> New Equation

{3x - y = 5

_________________

-4⁄7y = 1 1⁄7

-2 = y [Plug this back into both equations above to get the x-coordinate of 1]; 1 = x

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2.

{βˆ’3x + 9y = 36

{4x + 12y = 24

ΒΎ[4x + 12y = 24]

{βˆ’3x + 9y = 36

{3x + 9y = 18

______________

18y = 54

___ ___

18 18

y = 3 [Plug this back into both equations above to get the x-coordinate of βˆ’3]; βˆ’3 = x

__________________________________________________________

1.

{4x βˆ’ y = βˆ’38

{x + y = 3

_____________

5x = -35

___ ____

5 5

x = -7 [Plug this back into both equations above to get the y-coordinate of 10]; 10 = y

I am joyous to assist you anytime.