Solving Linear Equations with Substitution

The video tutorial explains how to solve a system of equations using the substitution method. It begins with an introduction to the concept, followed by presenting the problem: two equations, -3x-4y=-2 and y=2x-5. The instructor rewrites the equations, substitutes the value of y from the second equation into the first, and solves for x. After finding x=2, the instructor uses this value to solve for y, resulting in y=-1. The solution is verified by substituting the values back into the original equations, confirming their correctness. The tutorial concludes with a humorous remark about not being outsmarted by talking birds.

What is the purpose of the exercise introduced in the video?

• To learn about talking birds

• To solve systems of equations with substitution

• To practice multiplication

• To understand fractions

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What are the given equations in the exercise?

• 3x - 2y = 1 and y = x + 2

• x + y = 5 and 2x - y = 3

• -3x - 4y = -2 and y = 2x - 5

• y = 3x + 4 and x = 2y - 5

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Why is it convenient that the second equation is already solved for y?

• It makes it easier to substitute y in the first equation

• It eliminates the need to solve for x

• It allows us to ignore the first equation

• It simplifies the multiplication process

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the first step after rewriting the equations?

• Solving for y

• Substituting y in the first equation

• Combining like terms

• Multiplying both sides by 2

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the result of distributing -4 in the equation -3x - 4(2x - 5) = -2?

• -3x - 8x + 20

• -3x + 8x - 20

• -3x - 8x - 20

• -3x + 8x + 20

Tags

CCSS.6.EE.A.3

What is the value of x after solving the equation -11x + 20 = -2?

• x = -2

• x = 2

• x = -1

• x = 1

Tags

CCSS.7.EE.B.4A

Which equation is used to solve for y after finding x?

• 2x - y = 3

• -3x - 4y = -2

• y = 2x - 5

• x + y = 5

What is the value of y when x = 2?

• y = 2

• y = 0

• y = -1

• y = 1

How can you verify that the solution (x=2, y=-1) is correct?

• By substituting x and y into the first equation only

• By checking if x and y are positive

• By substituting x and y into both equations

• By substituting x and y into the second equation only

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the final step after verifying the solution?

• Multiplying both sides by -1

• Typing the solution to confirm

• Rewriting the equations

• Ignoring the solution