Question

Question 3(Multiple Choice Worth 4 points)

Answer 1

Answer:

The solution of the system of equations is:

                          negative 6 over 5 comma negative 8 over 5.

Step-by-step explanation:

We are given a system of linear equations as:

                          2x + y = −4 ------------(1)

                         y = 3x + 2------------(2)

Now we solve the system of equations using the substitution method.

i.e. we substitute the value of y in terms of x from equation (2) in equation (1) and find the value of x and y.

i.e.

2x+3x+2= -4

i.e.  5x+2= -4

i.e.  5x= -6

i.e.  x= -6/5

Similarly, on putting this value of x in equation (2) we obtain:

y= -8/5

               Hence, the solution is:

                           $(-\dfrac{6}{5},-\dfrac{8}{5})$

Answer 2

Subsitution

y=3x+2
subsitute (3x+2) for y in other equation

2x+y=-4
2x+(3x+2)=-4
2x+3x+2=-4
5x+2=-4
minus 2 both sides
5x=-6
divide both sides by 5
$x=\frac{-6}{5}$

subsitute back

$y=3x+2$
$y=3(\frac{-6}{5})+2$
$y=\frac{-18}{5}+2$
$y=\frac{-18}{5}+\frac{10}{5}$
$y=\frac{-18+10}{5}$
$y=\frac{-8}{5}$


$x=\frac{-6}{5}$
$y=\frac{-8}{5}$

(x,y)
$(\frac{-6}{5},\frac{-8}{5})$



the solution is $(\frac{-6}{5},\frac{-8}{5})$
that is the first option