All categories

3 years ago

X^2 - 6 = -2x Find the solution by completing the square

Mathematics

1 answer:

Lunna [17]3 years ago

6 0

Answer:

x = -1±sqrt( 7)

Step-by-step explanation:

x^2 - 6 = -2x

Add 2x to each side

x^2 +2x- 6 = -2x+2x

x^2 +2x -6 = 0

Add 6 to each side

x^2 +2x- 6+6 = 6

x^2 +2x = 6

Take the coefficient of x

Divide by 2

2/2 =1

Square it

1^2 =1

Add this to each side

x^2+2x+1 = 6+1

(x+1)^2 = 7

Take the square root of each side

sqrt((x+1)^2) =±sqrt( 7)

x+1 = ±sqrt( 7)

Subtract 1 from each side

x+1-1 = -1 ±sqrt( 7)

x = -1±sqrt( 7)

You might be interested in

11 nickels to 11 dimes are what ratio?

castortr0y [4]

Answer: 11:11

Step-by-step explanation:

The ratio is 11 nickles to 11 dimes, Take away the names of the coins and there is your answer. (If i'm correct)

7 0

3 years ago

Read 2 more answers

The dimensions of a square are altered so that one dimension is increased by 7 feet, while the other is decreased by 2 feet. The

Kamila [148]

Answer:

the original area is 64ft squared or 169ft squared more perdurable 64

Step-by-step explanation:

(x-2)(x+7)=90

x^2 +5x -14=90

x^2 +5x -14 -90=90-90

x^2 +5x -104=0

factor it out

(x−8)(x+13)=0

so 8 or -13

4 0

3 years ago

Aaron has 16 blue pens and 12 red pens.

Maslowich

Answer:

Step-by-step explanation:

16÷4=4 12÷3=4 meaning is.the lowest common multiple

7 0

2 years ago

Perform the following operations and write the answers in radical form. Part A:√7+√3+√98−√18 Part B:3√5−3√11+2√121−3√90

Sveta_85 [38]

Answer:

$\sqrt{7}+\sqrt{3}+4\sqrt{2}$
$3\sqrt{5}-3\sqrt{11}+22-9\sqrt{10}$

Step-by-step explanation:

Part A ;

$\sqrt{7} +\sqrt{3} +\sqrt{98} -\sqrt{18} \\\\\sqrt{98}=7\sqrt{2}\\\sqrt{18}=3\sqrt{2}\\\\=\sqrt{7}+\sqrt{3}+7\sqrt{2}-3\sqrt{2}\\\\\mathrm{Add\:similar\:elements:}\:7\sqrt{2}-3\sqrt{2}=4\sqrt{2}\\\\=\sqrt{7}+\sqrt{3}+4\sqrt{2}$

Part B ;

$3\sqrt{5} - 3\sqrt{11} + 2\sqrt{121} -3\sqrt{90} \\\\2\sqrt{121}=22\\3\sqrt{90}=9\sqrt{10}\\\\=3\sqrt{5}-3\sqrt{11}+22-9\sqrt{10}$

8 0

3 years ago

A biker’s speed is 1.5 times faster than a walker’s speed. They start moving simultaneously in the same direction from the same

worty [1.4K]

Let the walker’s speed be W, then the biker’s is W+1.5W=2.5W. Difference in speed is 1.5W. Distance=speed times time, so 12.5=1.5W×1.5=2.25W, and W=12.5/2.25=1250/225=50/9=5.56 mph. The biker’s speed is 2.5W=125/9=13.89 mph to 2 Dec places.
(Note: “1.5 times faster than a walker’s speed” could not reasonably mean the biker’s speed=1.5W because this would give W=16.67 mph, which is very fast for a runner, let alone a walker (!), and a biker’s speed of 25mph.)

5 0

3 years ago

Read 2 more answers