Mr. Elder
PROVINCIAL EXAM MATERIAL
Math 10
Mathematics 10
Unit 3.8 – Factoring Special Polynomials KEY
Last class you worked on factoring trinomials when a GCF could not be found and removed.
Today we will look at the last of the special factoring cases you will need to know about.
What is different about the following trinomial 
It has two variables instead of one.
Thankfully, this does not change a thing about how we solve it.
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STOP! Do questions #1 – 4 on the practice worksheet
What do you notice about the following trinomial?
Both first and last terms are perfect squares.
We call this a perfect square trinomial.
If you find a question to look like this, then we follow a special set of rules.
What does it mean to be a perfect square?  Same thing multiplied by itself
This means we will need the exact same numbers/signs inside both sets of
brackets in our binomial.
All we do is square root the first and last terms and these values take the first and
second place inside the binomial brackets.
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PROVINCIAL EXAM MATERIAL
Mr. Elder
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What about
Math 10
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**don’t rearrange this time
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STOP! Do questions #5 – 8 on the practice worksheet
The second last special case we need to look at involves what appears to be a binomial, but
is in fact a perfect square trinomial.
So we need two factors that multiply to
but add to
What do we know about these two numbers right away?
They must be the same number just one positive and one negative
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What about
Factor out the GCF
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STOP! Do questions #9 – 12 on the practice worksheet
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Mr. Elder
PROVINCIAL EXAM MATERIAL
Math 10
The last special case we need to look at is when you get a trinomial that looks like the
following:
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STOP! Do questions #13 – 16 on the practice worksheet
Homework: pg. 194/5, #4ab, 6ad, 8ae,
10ag, 11af, 12ab, 13ad, 20, 21
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