Answers NC-Math 2Solving Linear Systems by Substitution

Solving Linear Systems by Substitution — Unit test Answers

0 verified answers

Free Preview

Brandi is downloading music for her MP3 player. Albums cost $10 each, and singles cost $1 each. She wants to purchase at least 5 singles but wants to spend no more than $25 total. If Brandi purchases x albums and y singles, which of the following is a possible combination of albums and singles that Brandi could purchase and stay within her guidelines?

5 albums and 2 singles

2 albums and 5 singles

2 albums and 10 singles

10 albums and 2 singles

Free Preview

Which graph represents the solution of x2 + (y – 2)2 8x?

On a coordinate plane, a circle has center (0, 2) and radius 3. A parabola opens to the right and goes through (8, 8), has vertex (0, 0), and goes through (4, negative 6). Everything inside of the circle and inside of the parabola is shaded.

On a coordinate plane, a circle has center (2, 0) and radius 6. A parabola opens to the right and goes through (8, 8), has vertex (0, 0), and goes through (4, negative 6). Everything inside of the circle and outside of the parabola is shaded.

Option

Review the graph.

y ≤ x2 – 8 and x > y2 + 1

y ≥ x2 – 8 and x < y2 + 1

y ≤ x2 + 1 and x > y2 – 8

y ≥ x2 + 1 and x < y2 – 8

Evan washes two types of vehicles. It takes him 30 minutes to wash a car and 40 minutes to wash a truck. He charges $12 to wash a car and $15 to wash a truck. In 270 minutes, Evan made $105 washing cars and trucks. How many trucks did Evan wash?

2 trucks

3 trucks

4 trucks

5 trucks

A pair of weak earthquakes is modeled by a system of inequalities. One earthquake occurred roughly 20 km east and 14 km north of the center of Columbia, NC. The quake could be felt from 25 km away. A couple days later, another earthquake occurred 8 km west and 3 km north of the center of Columbia and could be felt from 14 km away. If Columbia is located at (0, 0) on a coordinate grid, the system of inequalities represents this scenario.

4 km west and 12 km south

6 km west and 4 km north

2 km east and 10 km north

6 km east and 8 km north

Which system of equations is consistent and dependent?

mc014-1.jpg

mc014-2.jpg

mc014-3.jpg

mc014-4.jpg

What is the value of y in the solution to the following system of linear equations?

A school district needs to arrange transportation for at least 360 students for a field trip. The district can use large buses or small buses. The large buses hold 60 students each and have an operating expense of $300 for the day. The small buses hold 45 students each and have an operating expense of $200 for the day. The district only has chaperones for, at most, seven buses. What is the minimum cost for the transportation for the field trip if each bus has chaperones?

$1,400

$1,600

$1,700

$1,800

A cell phone carrier offers two plans for text messaging. Plan A costs $20 per month plus $0.05 per text. Plan B costs $10 per month plus $0.10 per text. For how many text messages per month are the plans the same cost?

200

300

Which graph represents the solution to the system of inequalities?

On a coordinate plane, a curve approaches the x-axis in quadrant 2 and increase through (0, 1) and (2, 9). An ellipse has center (0, 0) and goes through (4, 0), (0, negative 8), (negative 4, 0), and (0, 8). Everything inside of the ellipse and below the curve is shaded.

On a coordinate plane, a curve approaches the x-axis in quadrant 2 and increase through (0, 1) and (2, 9). An ellipse has center (0, 0) and goes through (8, 0), (0, negative 4), (negative 8, 0) and (0, 4). Everything inside of the ellipse and below the curve is shaded.