contestada

In the system of equations below, I want to eliminate the variable y.
3x + 5y = 2
6x - 10y = -16
The first step to solving this system of equations is multiplying the first equation
by a number other than -1. Which number would that be?
The answer choices are..
-2
5
-5
2
0 -5
2.

Respuesta :

Answer:

(x,y)=(-1,1)

Step-by-step explanation:

Given that,

3x + 5y = 2   .....(1)

6x - 10y = -16  ....(2)

Finding the value of x from equation (1).

[tex]x=\dfrac{2-5y}{3}[/tex]

Put the value of x in equation (2)

[tex]6(\dfrac{2-5y}{3}) - 10y = -16\\\\2(2-5y)-10y=-16\\\\4-10y-10y=-16\\\\-20y=-16-4\\\\y=1[/tex]

Put the value of y in equation (1) :

[tex]3x + 5(1) = 2\\\\3x=2-5\\\\3x=-3\\\\x=-1[/tex]

So, the solution of the equations is (-1,1).