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Advanced Math · Polynomial Expressions And Equations

SAT Polynomial Expressions And Equations Practice Questions (Free + Explanations) | Quiz 8

Question 12345 of 5

Question 1 of 5

The graph of a parabola crosses the -axis at and . The point where the parabola crosses the -axis is . Which equation could represent this parabola?

Explanation

Since the parabola crosses the -axis at and , its equation can be written in factored form as for some constant . Using the point where it crosses the -axis, , substitute and :

So , and the equation is

Concept summary

A quadratic with -intercepts and can be written as . Use another point to find the value of .

Question 2 of 5

A park manager is designing a rectangular flower bed next to a straight walkway, so fencing is needed on only three sides. The manager has feet of fencing available. If the area of the flower bed, in square feet, is modeled by the polynomial , where is the width of the bed perpendicular to the walkway, what is the maximum possible area of the flower bed?

Explanation

The area function is

This is a quadratic that opens downward, so its maximum value occurs at the vertex. For

the vertex has -coordinate

Then the maximum area is

So the maximum possible area is square feet.

Concept summary

A quadratic model can represent area in a geometric setting, and when the parabola opens downward, the maximum value is found at the vertex.

Question 3 of 5

For a polynomial , the remainder when is divided by is , and the remainder when is divided by is . Which expression must be equivalent to for some polynomial ?

Explanation

Because the remainders on division by and are known, the Remainder Theorem gives and . If is factored out, the remaining part must be a linear expression, since any polynomial can be written in the form

Then substituting the two given values gives

and

Solving this system: subtract the second equation from the first to get , so . Then , so . Therefore

which matches the correct expression.

Concept summary

When a polynomial is divided by two linear factors, it can be written as the product of those factors times another polynomial plus a linear remainder. Use the given remainders with the Remainder Theorem to determine that linear expression.

Question 4 of 5

A ball is launched upward from ground level. Its height above the ground, in feet, is modeled by a polynomial function of time , in seconds. The graph of has -intercepts at and , and the point lies on the graph. Which function could represent ?

Explanation

Because the graph has intercepts at and , the function must include factors and . So can be written as . Using the point gives

so . Therefore,

This function also makes sense for the situation because the parabola opens downward, so the ball rises and then falls back to the ground.

Concept summary

For a polynomial interpreted from a graph, use the intercepts to determine factors, then use a known point to find the constant multiplier and check that the graph's shape fits the context.

Question 5 of 5

A monic cubic polynomial has the form , where , , and are constants. When is divided by , the remainder is . When is divided by , the remainder is . If is also a factor of , what is the value of ?

Explanation

Use the Remainder Theorem and the given factors. Since the remainder when dividing by is , . Since division by leaves remainder , , so is a factor. Also, is a factor, so . Because the polynomial is monic and cubic, it must be

for some number . Now use :

So

Thus

To find , expand:

so

Therefore, , , and , and

Concept summary

For a polynomial, the remainder when dividing by is . If is a factor, then . These conditions can be used together to build and solve a system for unknown roots or coefficients.

Your results

0of 5 correct

Estimated SAT Math band

500-550

Illustrative range from this short quiz—not an official College Board score.

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Your results

1of 5 correct

Estimated SAT Math band

500-550

Illustrative range from this short quiz—not an official College Board score.

Adaptive practice, weak-area review, and timed tests live in the MCQsLearn app—pick up where you left off on your phone.

More SAT Math practice

Your results

2of 5 correct

Estimated SAT Math band

600-650

Illustrative range from this short quiz—not an official College Board score.

Adaptive practice, weak-area review, and timed tests live in the MCQsLearn app—pick up where you left off on your phone.

More SAT Math practice

Your results

3of 5 correct

Estimated SAT Math band

600-650

Illustrative range from this short quiz—not an official College Board score.

Adaptive practice, weak-area review, and timed tests live in the MCQsLearn app—pick up where you left off on your phone.

More SAT Math practice

Your results

4of 5 correct

Estimated SAT Math band

700+

Illustrative range from this short quiz—not an official College Board score.

Adaptive practice, weak-area review, and timed tests live in the MCQsLearn app—pick up where you left off on your phone.

More SAT Math practice

Your results

5of 5 correct

Estimated SAT Math band

700+

Illustrative range from this short quiz—not an official College Board score.

Adaptive practice, weak-area review, and timed tests live in the MCQsLearn app—pick up where you left off on your phone.

More SAT Math practice