AnswersCR27 ALG 1-1200310-S2-Degele-VOL7006PChapter 9 Unit TEST: Solving Quadratic Equations

Chapter 9 Unit TEST: Solving Quadratic Equations Answers

0 verified answers1 views
1
Free Preview

Which shows the correct substitution of the values a, b, and c from the equation –2 = –x + x2 – 4 into the quadratic formula?Quadratic formula: x =

Question illustration
A
x = StartFraction negative (negative 1) plus or minus StartRoot (negative 1) squared minus 4 (1)(negative 4) EndRoot Over 2(1) EndFraction
Option A
B
x = StartFraction negative 1 plus or minus StartRoot 1 squared minus 4 (negative 1)(negative 4) EndRoot Over 2(negative 1) EndFraction
Option B
C
x = StartFraction negative (negative 1) plus or minus StartRoot (negative 1) squared minus 4 (1)(negative 4) EndRoot Over 2(1) EndFraction
Option C
D
x = StartFraction negative (negative 1) plus or minus StartRoot (negative 1) squared minus 4 (1)(negative 2) EndRoot Over 2(1) EndFraction
Option D
2
Free Preview

Rounded to the nearest hundredth, what is the positive solution to the quadratic equation 0=2x2+3x-8?Quadratic formula: x =

Question illustration
A
1.39
B
2.00
C
2.89
D
3.50
3

What are the values of a, b, and c in the quadratic equation 0 = 5x – 4x2 – 2?

A
a = 5, b = 4, c = 2
B
a = 5, b = –4, c = –2
C
a = –4, b = 5, c = –2
D
a = 4, b = –5, c = –2
4

Zacharias is using the quadratic formula to solve the equation 0 = –2x2 + 5x – 3. He begins by substituting as shown.Quadratic formula: x = Substitution:

Question illustration
A
The –5 should be 5.
B
The 52 should be –52.
C
The 2 in the numerator should be –2.
D
The 2 in the denominator should be –2.
5

Which is a zero of the quadratic function f(x) = 9x2 – 54x – 19?

A
x =
Option A
B
x = 3
Option B
C
x = 6
Option C
D
x = 9
Option D
6

Isoke is solving the quadratic equation by completing the square.10x2+40x-13=010x2+40x=13A(x2+4x)=13

A
-13
B
4
C
10
D
40
7

Brianna is graphing the function f(x) = x2 + 6x + 5. What x-intercepts should Brianna use to graph f(x)?

A
–5 and –1
B
–5 and 1
C
–1 and 5
D
1 and 5
8

A function g(x) has x-intercepts at (, 0) and (6, 0). Which could be g(x)?

Question illustration
A
g(x) = 2(x + 1)(x + 6)
B
g(x) = (x – 6)(2x – 1)
C
g(x) = 2(x – 2)(x – 6)
D
g(x) = (x + 6)(x + 2)
9

Solve x2 – 8x = 3 by completing the square. Which is the solution set of the equation?

A
(4 minus StartRoot 19 EndRoot comma 4 + StartRoot 19 EndRoot)
Option A
B
(4 minus StartRoot 11 EndRoot comma 4 + StartRoot 11 EndRoot)
Option B
C
(4 minus StartRoot 8 EndRoot comma 4 + StartRoot 8 EndRoot)
Option C
D
(4 minus StartRoot 3 EndRoot comma 4 + StartRoot 3 EndRoot)
Option D
10

Solve x2 = 12x – 15 by completing the square. Which is the solution set of the equation?

A
(negative 6 minus StartRoot 51 EndRoot comma negative 6 + StartRoot 51 EndRoot)
Option A
B
(negative 6 minus StartRoot 21 EndRoot comma negative 6 + StartRoot 21 EndRoot)
Option B
C
(6 minus StartRoot 51 EndRoot comma 6 + StartRoot 51 EndRoot)
Option C
D
(6 minus StartRoot 21 EndRoot comma 6 + StartRoot 21 EndRoot)
Option D
11

A group of students is given a 10 by 10 grid to cut into individual unit squares. The challenge is to create two squares using all of the unit squares. Their teacher states that after the two new squares are formed, one should have a side length two units greater than the other.

A
x2 + (x – 2)2 = 10
B
x2 + 2x2 = 10
C
x2 + (x – 2)2 = 100
D
x2 + 2x2 = 100
12

A rectangle has an area of 40 square units. The length is 6 units greater than the width.

A
8 by 5
B
10 by 4
C
11 by 9
D
13 by 7
13

Which are the roots of the quadratic function f(q) = q2 – 125? Select two options.

Question illustration
A
q = 5
Option A
B
q = -5
Option B
C
q = 3
Option C
D
q = -3
Option D
E
q = 25
Option E
14

The product of two consecutive integers is 420. Which quadratic equation can be used to find x, the lesser number?

A
x2 + 1 = 420
B
x2 + 2 = 420
C
x2 + x = 420
D
x2 + 2x = 420
15

A rectangle’s length is three times its width, w. Its area is 243 square units. Which equation can be used to find the width of the rectangle?

A
w2 = 3(243)
B
3w2 = 243
C
4w2 = 243
D
3w2 = 3(243)
16

Which equation results from taking the square root of both sides of (x – 9)2 = 81?

A
x – 9 = ±9
B
x + 9 = ±9
C
x + 3 = ±9
D
x – 3 = ±9
17

What number should be added to both sides of the equation to complete the square? x2 + 12x = 11

Answer not available
18

Which equations are true for x = –2 and x = 2? Select two options

A
x2 – 4 = 0
B
x2 = –4
C
3x2 + 12 = 0
D
4x2 = 16
E
2(x – 2)2 = 0
19

What are the solution(s) of the quadratic equation 98 – x2 = 0?

A
x =
Option A
B
x =
Option B
C
x =
Option C
D
no real solution
20

Which shows the correct substitution of the values a, b, and c from the equation 0 = 4x2 + 2x – 1 into the quadratic formula below?Quadratic formula: x =

Question illustration
A
x = StartFraction negative 2 plus or minus StartRoot 2 squared minus 4(4)(negative 1) EndRoot Over 2(4) EndFraction
Option A
B
x = StartFraction negative 2 plus or minus StartRoot 2 squared minus 4(4)(1) EndRoot Over 2(4) EndFraction
Option B
C
x = StartFraction negative 2 plus or minus StartRoot 2 squared + 4(4)(negative 1) EndRoot Over 2(4) EndFraction
Option C
D
x = StartFraction negative 2 plus or minus StartRoot negative 2 squared minus 4(4)(negative 1) EndRoot Over 2(4) EndFraction
Option D

Did you find these answers helpful?