Systems Of Equations Math Worksheet (Page 2 of 3) in pdf

Systems Of Equations Math Worksheet Page 2

2x + 3 = x + 2

Since “y” is equal to both 2x + 3 and x + 2, then they are

equal to each other! Then, we can solve for “x” and plug our

value back into either equation to get “y”. It doesn’t matter

which, as we should get the same “y” value either way.

y = (_____) + 2 =

So, my point, is (____, ____).

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Let’s try this same idea on example 2. We can solve for

Ex 2:

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“y” in either equation above, since the coefficient of “y” is

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“1” in both of them, so I’ll use the first: 2x + y = 5

2x + y = 5

y = ________ Å

Now that we’ve found what “y” is equal to, let’s plug it in the

second equation, 2x + y = 7.

2x + (________) = 7 Again, distribute as necessary and

solve for “x”, if possible. In this case, however, see how the

“x”s cancel out? Here we ended up with a statement that is

false. Therefore, there are no places where the lines cross.

Sometimes, we get a true statement instead of a false

statement. In this case, the lines cross everywhere, or are

the same line. This would be the case with example 3.

Using substitution on example 3 is not fun. Here is why.

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If we solve either of the equations for either “x” or “y”, then

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we end up with fractions. Blar! -

= x

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2x – 3y = 8 is either

(and so is 4x – 6y = 16, actually).

Either way, plugging in fractions is not necessarily a good time. Luckily, there is

yet another way to do these that works every time and mostly eliminates having to

work with fractions.

Systems Of Equations Math Worksheet Page 2