Question 129601This question is from textbook Algebra 1
: I don't understand how to work this problem which is on page 408 systems of linear equations by substitution the problems is y=3x x=3y This question is from textbook Algebra 1
You can put this solution on YOUR website! Given to solve:
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The second equation is solved for x. It says that x equals 3y. So you can take 3y and substitute
it for x in the first equation. When you do, the first equation becomes:
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So this equation is:
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The only real value of y that will satisfy this equation is y = 0. If y does equal zero,
then both sides of the equation are equal to zero. Another way to look at this
is to start with:
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Subtract y from both sides and you have:
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Solve for y by dividing both sides by 8 and you have:
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Now that you know y equals zero you can return to either of the two equations you were
originally given and substitute 0 for y. If you do, you will find that x also equals zero.
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So the common solution for these two equations is (0, 0) meaning that the graphs of the two
equations intersect at the origin.
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Hope this helps you to understand the problem.
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