Which ordered pair is a solution for the system of equations? {3x−5y=152x−y=−4 (−5, −6) (0, 3) (2, 8) (−6, −11)

3x-5y =15

2x-y=-4
multiply the equation by 5 and then subtract equation 2 from equation 1
so 3x-5y =15
10x-5y =-20
-7x =35 x =-5
plug in the value of x in the second equation -10 -y =-4 - y= -4 +10 y =-6
x=-5 y=-6

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Phoca Phoca · Answer 2 · 2018-12-24T12:33:57+01:00

Answer:

(−5, −6)

Step-by-step explanation:

GIVEN : [tex]3x-5y = 15[/tex]

[tex]2x-y = -4[/tex]

SOLUTION:

[tex]3x-5y = 15[/tex] ------EQUATION 1

[tex]2x-y = -4[/tex] ------ EQUATION 2

Now multiply the equation 2 by 5

⇒ [tex]5(2x-y = -4)[/tex]

⇒[tex]10x-5y = -20[/tex] ---(a)

Now , subtract (a) from equation i.e

[tex]3x-5y-15-(10x-5y+20) = 0[/tex]

[tex]3x-5y-15-10x+5y-20) = 0[/tex]

[tex] -7x-35 = 0[/tex]

[tex] -7x=35[/tex]

[tex]x=\frac{35}{-7}[/tex]

[tex] x=-5 [/tex]

put x = - 5 in equation 1 to get value of y

[tex]3(-5)-5y = 15[/tex]

[tex]-15-5y = 15[/tex]

[tex]-5y = 15+15[/tex]

[tex]-5y = 30[/tex]

[tex]y = \frac{30}{-5}[/tex]

[tex]y = -6[/tex]

Thus (x,y) =(-5,-6) is a solution.