Solving Quadratic Equations by Square Roots

How do we undo something that is squared?

• Multiplication

• Square it

• Take the square root

• Division

Tags

CCSS.HSA.APR.B.3

CCSS.HSA.REI.B.4

What is the difference between a root and a square root?

• A root is half of a square root

• A root is a solution and square root undoes a square

• A root undoes a square and a square root is solution

• They are the same thing

How do we solve for x?

• It is already solved

• Divide it by 2

• Square it

• Take the square root

Tags

CCSS.HSA.REI.B.4

What are the roots of this Quadratic Equation?

• x = 6

• x = 4

• x = - 4

• x = -6

What is the first step for finding the roots of the quadratic equation?

• subtract 3 to both sides

• add 3 to both sides

• take the square root of both sides

• divide by 2

What are the roots of this quadratic equation?

• x = - 6

  x = 2

• x = 2,

  x = - 4

• x = -2,

  x = 4

• x = -2,

  x = 6

For this quadratic equation, we said that there are NO REAL SOLUTIONS. Why did we say that?

• Because 3 goes into 9, so those cancel out

• Because we cannot take the square root of a negative number

• Because a has to be equal to 1

• Because there is no c value

Tags

CCSS.HSA.REI.B.4

What is the error made when saving this quadratic equation?

• There should be 2 answers, because the square root of 9 is -3 and 3

• Taking the square root should always be the first step

• 21 -3 is not 18 so that was a mistake from the start

• The answer should be x = - 4 because the square root of 9 is -3

Tags

CCSS.HSA.REI.A.2

CCSS.HSA.REI.B.4

What is the error made when solving this quadratic equation?

• The answer should only be -2 since the square root of -4 is -2

• The answer should only be 2, because the native cancels out, since we took the square root of a negative

• There is no error, everything was done correctly

• The answer should be no real solutions, since we can't take the square root of a negative

Tags

CCSS.HSA.REI.A.2

CCSS.HSA.REI.B.4

What is this symbol called?

• Square Root

• Root

• Square

• Factor

Tags

CCSS.HSN.RN.A.1

CCSS.HSN.RN.A.2