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15 votes
Find the solution to the system of equations.

-8x + 4y = 24

-7x + 7y = 28.

please answer accurately with full explanation. don't spam ​

User Sgbj
by
3.0k points

2 Answers

18 votes
18 votes

Answer:

1) 2x - y + 6 = 0

2) x - y + 4 = 0

Explanation:

1) -8x + 4y = 24

= -8x + 4y - 24 = 24 - 24

= -8x + 4y - 24 = 0

= (-8x + 4y - 24) ÷ 4 = 0 ÷ 4

= -8x ÷ 4 + 4y ÷ 4 - 24 ÷ 4 = 0

= -2x + 4y ÷ 4 - 24 ÷ 4 = 0

= -2x + y - 24 ÷ 4 = 0

= -2x + y - 6 = 0

= 2x - y + 6 = 0

2) -7x + 7y = 28

= -7x + 7y - 28 = 28 - 28

= -7x + 7y - 28 = 0

= (-7x + 7y - 28) ÷ 7 = 0 ÷ 7

= -7x ÷ 7 + 7y ÷ 7 - 28 ÷ 7 = 0 ÷ 7

= -7x ÷ 7 + 7y ÷ 7 - 28 ÷ 7 = 0

= -x + 7y ÷ 7 - 28 ÷ 7 = 0

= -x + y - 28 ÷ 7 = 0

= -x + y - 4 = 0

= x - y + 4 = 0

User Dominik Traskowski
by
3.2k points
21 votes
21 votes

Answer:

x = -2, y = 2

Explanation:

-7x + 7y = 28

7y = 28 + 7x

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

-8x+4y=24 -----(2)

sub (1) into (2)

-8x+4(4+x)=24

-8x+16+4x = 24

-8x+4x = 24-16

-4x = 8

x = -2

sub x = -2 into (1)

y=4+(-2) = 2

User Ionaru
by
3.3k points