Respuesta :

Answer:

Step-by-step explanation:

7x+3y=3,3-y=7

7x+3y=3

7x=-3y+3

x=1/7(-3y+3)

x=-3/7y+3

x=-3/7y+3/7

-16/7y=40/7

y=-5/2

x=15/14+3/7

x=3/2

y=-5/2

x=3/2=1 1/2= 1.5

y=-5/2=-2 1/2= -2.5

msm555

Answer:

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

Step-by-step explanation:

To solve the simultaneous equations:

[tex] \begin{cases} 7x + 3y = 3 \\ 3x - y = 7 \end{cases} [/tex]

We can use the method of substitution or elimination. Here, I'll use the elimination method.

Multiply the second equation by 3 to eliminate [tex]y[/tex]:

[tex] \begin{cases} 7x + 3y = 3 \\ 9x - 3y = 21 \end{cases} [/tex]

Add the equations together:

[tex] (7x + 3y) + (9x - 3y) = 3 + 21 [/tex]

[tex] 7x + 3y + 9x - 3y = 24 [/tex]

[tex] 16x = 24 [/tex]

Solve for [tex]x[/tex]:

[tex] x = \dfrac{24}{16} [/tex]

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

Substitute [tex]x = \dfrac{3}{2}[/tex] into one of the original equations to solve for [tex]y[/tex]. Let's use the first equation:

[tex] 7\left(\dfrac{3}{2}\right) + 3y = 3 [/tex]

[tex] \dfrac{21}{2} + 3y = 3 [/tex]

[tex] 3y = 3 - \dfrac{21}{2} [/tex]

[tex] 3y = \dfrac{6 - 21}{2} [/tex]

[tex] 3y = -\dfrac{15}{2} [/tex]

[tex] y = -\dfrac{15}{6} [/tex]

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

So, the solution to the simultaneous equations is [tex] x = \dfrac{3}{2} [/tex] and [tex] y = -\dfrac{5}{2} [/tex].

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