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Solve the system by the elimination method. Check your work. 3a + 5b - 7 = 0 a - 2b - 4 = 0

User Sami N
by
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2 Answers

1 vote

Answer:

(34/11, -5/11)

Explanation:

3a + 5b - 7 = 0

a - 2b - 4 = 0 -multiply entire equation by -3 to eleminate a

-3a+6b+12=0

3a+5b-7=0

11b+5=0 subtract 5 on both sides

11b=-5

b=-5/11 now plug b into its place in the top equation

-3a+5(-5/11) -7=0 distribute

-3a-25/11-7=0 subtract 7 and -25/11

-3a-102/11=0 now add -102/11 to each side and divide by -3

-3a=-102/11

a= 34/11

User Aisin
by
7.9k points
4 votes
3a + 5b - 7 = 0
0a - 2b - 4 = 0

-2b = 4 - 0a
b = (4 - 0a)/ -2
b = -2

3a + 5b - 7 = 0
3a + 5(-2) - 7 = 0
3a - 10 - 7 = 0
3a - 17 = 0
3a = 17
a = 17/3 or 5 2/3

User Timotgl
by
7.7k points

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