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1. Solve this quadratic by factoring

6x^2+7x-5=0

2. Solve this quadratic by factoring x^2+5x-14=0

3. Solve this quadratic using the quadratic formula
3x^2-7x-9=0

4. Solve this quadratic by factoring
X^2-25=0

5. Solve this quadratic by factoring
X^2-6x=0

Please show work.

User Mathee
by
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1 Answer

1 vote

ANSWER #1:

x = -1.666666667

x = 0.5

STEP-BY-STEP:

Simplifying

6x2 + 7x + -5 = 0

Reorder the terms:

-5 + 7x + 6x2 = 0

Solving for variable 'x'.

(-5 + -3x)(1 + -2x) = 0

SUBPROBLEM 1

Set the factor '(-5 + -3x)' equal to zero and attempt to solve:

Simplifying

-5 + -3x = 0

Move all terms containing x to the left, all other terms to the right.

Add '5' to each side of the equation.

-5 + 5 + -3x = 0 + 5

Combine like terms:

0 + -3x = 0 + 5

-3x = 0 + 5

Combine like terms:

-3x = 5

Divide each side by '-3'.

x = -1.666666667

Simplifying

x = -1.666666667

SUBPROBLEM 2

Set the factor '(1 + -2x)' equal to zero and attempt to solve:

Simplifying

1 + -2x = 0

Move all x terms to the left, all other terms to the right.

Add '-1' to each side of the equation.

1 + -1 + -2x = 0 + -1

Combine like terms:

0 + -2x = 0 + -1

-2x = 0 + -1

Combine like terms:

-2x = -1

Divide each side by '-2'.

x = 0.5

Simplifying

x = 0.5

ANSWER #2:

x = -7

x = 2

STEP-BY-STEP:

Simplifying

x2 + 5x + -14 = 0

Reorder the terms:

-14 + 5x + x2 = 0

Solving for variable 'x'.

Factor a trinomial.

(-7 + -1x)(2 + -1x) = 0

SUBPROBLEM 1

Set the factor '(-7 + -1x)' equal to zero and attempt to solve:

Simplifying

-7 + -1x = 0

Solving

-7 + -1x = 0

Move all x terms to the left, all other terms to the right.

Add '7' to each side of the equation.

-7 + 7 + -1x = 0 + 7

Combine like terms:

0 + -1x = 0 + 7

-1x = 0 + 7

Combine like terms:

-1x = 7

Divide each side by '-1'.

x = -7

Simplifying

x = -7

SUBPROBLEM 2

Set the factor '(2 + -1x)' equal to zero and attempt to solve:

Simplifying

2 + -1x = 0

Solving

2 + -1x = 0

Move all x terms to the left, all other terms to the right.

Add '-2' to each side

2 + -2 + -1x = 0 + -2

Combine like terms:

0 + -1x = 0 + -2

-1x = 0 + -2

Combine like terms:

-1x = -2

Divide each side by '-1'.

x = 2

Simplifying

x = 2

ANSWER #3:

x = 3.25

x = -0.92

STEP-BY-STEP

Simplifying

3x2 + -7x + -9 = 0

Reorder the terms:

-9 + -7x + 3x2 = 0

Solving for variable 'x'.

Divide each side by '3'.

-3 + -2.333333333x + x2 = 0

Add '3' to each side

-3 + -2.333333333x + 3 + x2 = 0 + 3

Reorder the terms:

-3 + 3 + -2.333333333x + x2 = 0 + 3

Combine like terms:

0 + -2.333333333x + x2 = 0 + 3

-2.333333333x + x2 = 0 + 3

Combine like terms:

-2.333333333x + x2 = 3

The x term is -2.333333333x. Take half its coefficient (-1.166666667).

Square it (1.361111112) and add it to both sides.

Add '1.361111112' to each side

-2.333333333x + 1.361111112 + x2 = 3 + 1.361111112

Reorder the terms:

1.361111112 + -2.333333333x + x2 = 3 + 1.361111112

Combine like terms:

1.361111112 + -2.333333333x + x2 = 4.361111112

Factor a perfect square on the left side:

(x + -1.166666667)(x + -1.166666667) = 4.361111112

Calculate the square root of the right side: 2.088327348

Break this problem into two subproblems by setting

(x + -1.166666667) equal to 2.088327348 and -2.088327348.

SUBPROBLEM 1

x + -1.166666667 = 2.088327348

Simplifying

x + -1.166666667 = 2.088327348

Reorder the terms:

-1.166666667 + x = 2.088327348

Solving for variable 'x'.

Move all x terms to the left, all other terms to the right.

Add '1.166666667' to each side

Combine like terms:

0.000000000 + x = 2.088327348 + 1.166666667

x = 2.088327348 + 1.166666667

Combine like terms:

2.088327348 + 1.166666667 = 3.254994015

Simplifying

x = 3.254994015

SUBPROBLEM 2

x + -1.166666667 = -2.088327348

Simplifying

x + -1.166666667 = -2.088327348

Reorder the terms:

-1.166666667 + x = -2.088327348

Solving

-1.166666667 + x = -2.088327348

Solving for variable 'x'.

Move all x terms to the left, all other terms to the right.

Add '1.166666667' to each side of the equation.

-1.166666667 + 1.166666667 + x = -2.088327348 + 1.166666667

Combine like terms: -1.166666667 + 1.166666667 = 0.000000000

0.000000000 + x = -2.088327348 + 1.166666667

x = -2.088327348 + 1.166666667

Combine like terms: -2.088327348 + 1.166666667 = -0.921660681

x = -0.921660681

Simplifying

x = -0.921660681

ANSWER #4:

x = -5

x = 5

STEP-BY-STEP:

Simplifying

x2 + -25 = 0

Reorder the terms:

-25 + x2 = 0

Solving

-25 + x2 = 0

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '25' to each side

-25 + 25 + x2 = 0 + 25

Combine like terms: -25 + 25 = 0

0 + x2 = 0 + 25

x2 = 0 + 25

Combine like terms: 0 + 25 = 25

x2 = 25

Simplifying

x2 = 25

Take the square root of each side:

x = {-5, 5}

User LucSpan
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4.0k points