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1 vote
2y = 4x + 8 4y = 4x + 20

2 Answers

6 votes
2y = 4x + 8 ------> y = 2x + 4
4y = 4x + 20 ------> y = x+5

2x+4 =x+5
x = 1
y=x+5=1+5=6

Check:
2*6 = 4*1 + 8 , 12 =12
4*6 = 4*1 + 20, 24 =24

x=1,y=6
(1,6)


User Tamim
by
5.9k points
2 votes
2y = 4x + 8

Multiply 2 to both sides

(2)2y = 2(4x + 8)
4y = 8x + 16

Plug in 8x + 16 for 4y.

8x + 16 = 4x + 20

Isolate the x, subtract 4x from both sides and 16 from both sides

8x (-4x) + 16 (-16) = 4x (-4x) + 20 (-16)

8x - 4x = 20 - 16

4x = 4

divide 4 x from both sides to isolate the x

4x/4 = 4/4

x = 4/4

x = 1

Plug in 1 for x in one of the equations

2y = 4(1) + 8
2y = 4 + 8
2y = 12

isolate the y, divide 2 from both sides

2y/2 = 12/2

y= 12/2
y = 6

x = 1, y = 6 is your answer


hope this helps
User Michael Baker
by
5.3k points