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Please please help me!!

solve the system of equations by the substitution method.
{ 21x + 7y = 41
{ -3x = y + 6

Select the correct choice below and, if necessary, fill in the answer box to complete your choice.
A. The solution is __ ( type an ordered pair. Simplify your answer.)
B. There are infinitely many solutions.
C. There is no solution.

User Bhuvin
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1 Answer

3 votes

Answer:

C. There is no solution.

Explanation:

Similarly to the previous question, you want to substitute one of these equations into the other:

21x + 7y = 41

-3x = y + 6

But first, you need to isolate for a variable. I'm going to isolate for y in the second equation to avoid fractions.

-3x = y + 6

y = -3x - 6

Now that I've done that, I can now plug it into the first equation to solve for x:

21x + 7(-3x - 6) = 41

21x + -21x - 42 = 41

0x = 41

0 ≠ 41

Since 0 ≠ 41, these lines are parallel, which means that there are no solutions.

User Toadums
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5.3k points