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26 votes
26 votes
Solve the system of equations

1/2x+6y=12
y=x+15

Please I need help. Also if you know the answer could you help me learn how to solve it?

User TechnicalTophat
by
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2 Answers

20 votes
20 votes

Answer:

x=-12,y=3

Explanation:

1/2x+6y=12

y=x+15

since y=x+15

substitute y in first equation, we have

1/2x+6(x+15)=12

open the bracket

1/2x+6x+90=12

1/2x+6x=12-90

x/2+6x= -78

13x/2=-78

13x=2×-78

x=-12

Now x=-12, put x=-12 in the second equation, we have

y=x+15

y=-12+15

y=3

hope it helps

11 votes
11 votes

Answer:

x=-8, y=2

Explanation:

if 1/2x+6y=12 then 1/2x+y=2 and x+y=1 and y=1-x..if y=1-x then 1-x=x=15 and 2x=16 so x=8 if x=8 then 1/2(8) +6y=12 or 4=6y=12.. then 2y=4 and y=2

User Sebb
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3.0k points