# PSAT 1.10 Math Diagnostic

PSAT 1.10 Math Diagnostic. Which of the following is a factor of the expression?

 Algebra and Functions Operations on Algebraic Expressions Basic Algebra Algebraic Expressions Math Passport to Advanced Math Mathematics and Statistics Assessment Algebraic Expressions and Equations PSAT PSAT MathPSAT Math Diagnostic PSAT Math Math Diagnostic

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of the answer choices if they were a factor of

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Thanks guys Tactic number two we figure it out ourselves

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We know that if an expression is the factor of

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a polynomial any roots of the expression must be routes

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of the polynomial And a root of an expression is

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where the expression is equal to zero So if we

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want to test whether an expression is a factor of

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a polynomial we'll have to set it equal to zero

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and then solve for x Well after that we can

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substitute the value we get into the equation And if

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the whole thing ends up peopling zero then the expression

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is a factor or route of the polynomial down confusing

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and let's Just see it in action Going with option

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a x minus two if we set that equal to

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zero i e x minus two equals zero We would

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add to to both sides and get x equals two

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Now we just take our x value and substitute it

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into the original equation We get two cubed minus six

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times two Squared plus five times two plus twelve which

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simplifies to eight minus twenty four plus ten plus well

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and that whole jumbled mess comes out tio six Well

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whether or not it's a master of disguises six is

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no zero so is out We'll try the same thing

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with option b x plus one here will set that

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equal to zero then subtract one from both sides to

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get x equals negative one and we plug in negative

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one for ex well naked one cubed minus six times

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negative one squared plus five times negative one plus twelve

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as we get that all simplifies too negative one minus

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six minus five plus twelve which comes out to wait

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for it Zero that's the face of a winner We

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could do the same for option cnd but since we

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already found the one factor that works there's not really

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any need go further unless we're really starved for entertainment 00:02:15.53 --> [endTime] and maybe invest in an xbox