Question

Can you please solve these systems of equations using elimination for x and y?

1. 8x+2y=46
7x+3y=47

2. 4x+6y=62
7x+3y=47

3. 4x+6y=62
2x+6y=76

4. 8x+1y=43
2x+4y=98
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Answer 1

1.
`x\x=(22)/(5)=4.5, y=(27)/(5)=5.5`

2.
`x=(16)/(5)=3.2,y=(41)/(5)=8.3`

3. x=−7,y=15.

4.
`x=(37)/(15)=2(7)/(15),y=(349)/(15)=23(4)/(15)`

Explanation:

I hope this helps.

Answer 2

• (4.4, 5.4), (3.2, 8.3), (-7, 15), (23 4/15, 2 7/15)

Explanation:

1.

Multiply the first equation by 3/2:

• 3/2×8x + 3/2×2y = 3/2×46
• 12x + 3y = 69

Subtract the second equation:

• 12x - 7x = 69 - 47
• 5x = 22
• x = 4.4

Find y:

• 4*4.4 + y = 23
• y = 23 - 17.6
• y = 5.4

2.

Double the second equation and subtract the first one:

• 14x - 4x = 94 - 62
• 10x = 32
• x = 3.2

Find y:

• 4*3.2 + 6y = 62
• 6y = 62 - 12.8
• 6y = 49.8
• y = 8.3

3.

Subtract the second equation from the first one:

• 4x - 2x = 62 - 76
• 2x = -14
• x = -7

Find y:

• 4(-7) + 6y = 62
• 6y = 62 + 28
• 6y = 90
• y = 15

4.

Multiply the second equation by 4 and subtract the first one:

• 16y - y = 4(98) - 43
• 15y = 349
• y = 349/15
• y = 23 4/15

Find x:

• 8x + 23 4/15 = 43
• 8x = 19 11/15
• x = 2 7/15