Solving Word Problems with Systems of Equations

The video lesson guides students through solving a word problem involving the prices of boxes of lights, ornaments, and candles. It defines variables, sets up equations, and uses elimination and substitution methods to find the prices of each item. The lesson concludes with a word solution summarizing the findings.

What does the variable 'L' represent in the problem?

• The price of a box of ornaments

• The price of a box of lights

• The price of a box of candles

• The number of boxes of lights

Why is the variable 'N' used instead of 'O'?

• Because 'O' looks like a zero

• Because 'N' is easier to remember

• Because 'O' is already used for another variable

• Because 'N' is the first letter of 'ornaments'

Tags

CCSS.6.EE.B.6

What is the first step in solving the system of equations?

• Substitute values into the equations

• Solve for the variable L

• Eliminate the variable C

• Add all three equations together

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Which two equations are used in Step 1 to eliminate the variable C?

• All three equations

• Second and third equations

• First and second equations

• First and third equations

What is the result of eliminating C in Step 1?

• 3L - 2N = 11

• 5L + 7N = 44

• L - 3N = -13

• 2L + 4N = 20

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

In Step 2, what is the purpose of multiplying the second equation by -2?

• To simplify the equation

• To eliminate the variable C

• To eliminate the variable N

• To eliminate the variable L

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the simplified equation obtained in Step 2?

• 4L + 7N = 57

• 6L + 3N = 34

• 8L - N = 11

• 8L + N = 11

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the value of L after solving the simplified equations?

• 5

• 3

• 4

• 2

Tags

CCSS.7.EE.B.4A

What is the value of N after substituting L back into the equation?

• 6

• 5

• 4

• 3

Tags

CCSS.7.EE.B.4A

What is the final price of a box of candles?

• $7

• $6

• $5

• $8

Tags

CCSS.6.EE.B.6