Question

Solve each equation.

(x + 3)(x - 3) = 16 - 2x2

Answer 1

multiply left side things..
u will get
x2-9
now
x2-9=16-2x2
3x2=16+9
x2=25/3
x=+-5sqrt(1/3)

Answer 2

Simplifying
(x + 3)(x + -3) = 16 + -2x^2
Reorder the terms:
(3 + x)(x + -3) = 16 + -2x^2
Reorder the terms:
(3 + x)(-3 + x) = 16 + -2x^2
Multiply (3 + x) * (-3 + x)
(3(-3 + x) + x(-3 + x)) = 16 + -2x^2
((-3 * 3 + x * 3) + x(-3 + x)) = 16 + -2x^2
((-9 + 3x) + x(-3 + x)) = 16 + -2x^2
(-9 + 3x + (-3 * x + x * x)) = 16 + -2x^2
(-9 + 3x + (-3x + x^2)) = 16 + -2x^2
Combine like terms: 3x + -3x = 0
(-9 + 0 + x^2) = 16 + -2x^2
(-9 + x^2) = 16 + -2x^2
Solving
-9 + x^2 = 16 + -2x^2
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '2x^2' to each side of the equation.
-9 + x^2 + 2x^2 = 16 + -2x^2 + 2x^2
Combine like terms: x2 + 2x2 = 3x2
-9 + 3x2 = 16 + -2x2 + 2x2
Combine like terms: -2x2 + 2x2 = 0
-9 + 3x2 = 16 + 0
-9 + 3x2 = 16
Add '9' to each side of the equation.
-9 + 9 + 3x2 = 16 + 9
Combine like terms: -9 + 9 = 0
0 + 3x2 = 16 + 9
3x2 = 16 + 9
Combine like terms: 16 + 9 = 25
3x2 = 25
Divide each side by '3'.
x2 = 8.333333333
Simplifying
x2 = 8.333333333
Take the square root of each side:
x = {-2.886751346, 2.886751346}

Answer 3

Solve each equation.

0.2x2 + 1.2 = 3.4

Answer 4

Not really sure about this one...But here's my:
0.2x2 + 1.2 = 3.4 divide by 0.2=2/10 {that is multiply by 10/2}
x2+6=17 --> x2-11=0
(x-sqrt(11))(x+sqrt(11))=0

Answer 5

I have one more is that okay?

Answer 6

Go ahead:)

Answer 7

Solve each equation.

6x^2 + 1 = 13 and then

Solve this equation

4 = x^2 -7

Answer 8

For the first one:
Simplifying
6x2 + 1 = 13
Reorder the terms:
1 + 6x2 = 13
Solving
1 + 6x2 = 13
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '-1' to each side of the equation.
1 + -1 + 6x2 = 13 + -1
Combine like terms: 1 + -1 = 0
0 + 6x2 = 13 + -1
6x2 = 13 + -1
Combine like terms: 13 + -1 = 12
6x2 = 12
Divide each side by '6'.
x2 = 2
Simplifying
x2 = 2
Take the square root of each side:
x = {-1.414213562, 1.414213562}

Answer 9

I'm not sure about the second one...
@paki

Answer 10

it will be....
4 = x^2 -7
x^2=4+7
x^2=11... now take the root on both sides...

x=3.31.... @YanaSidlinskiy