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2 years ago

Q(–1, a) is 4 √5 units away from P(3, –2). Find all possible values of a.

Mathematics

1 answer:

vagabundo [1.1K]2 years ago

8 0

Answer:

a=6,-10

Step-by-step explanation:

$4\sqrt{5}=\sqrt{(3+1)^2+(-2-a)^2} \\squaring\\80=16+(2+a)^2\\80-16=(2+a)^2\\(a+2)^2=64\\taking~square ~root\\\\a+2=\pm 8\\either \\a+2=8,\\a=8-2=6\\or\\a+2=-8\\a=-8-2=-10$

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Question 6 of 10<br>2 Points<br>Which number is rational?<br>ОА. О.31243576.<br>оооо

MatroZZZ [7]

Answer:

Yes О.31243576 is a rational number

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2 years ago

If i^2 = −1 and x = i + 9, which is the result of squaring x?

Anestetic [448]

Answer:

80 + 18i

Step-by-step explanation:

i² = -1

x = i + 9

x² = (i + 9)²

Applying; (a + b)² = a² + 2ab + b² concept,

x² = i² + 18i + 81

We know that i² = -1

So x² = -1 + 18i + 81

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2 years ago

Solve this equation for x: 2x^2 + 12x - 7 = 0

zhannawk [14.2K]

Answer:

x=0.5355 or x=-6.5355

First step is to: Isolate the constant term by adding 7 to both sides

Step-by-step explanation:

We want to solve this equation: $2x^2 + 12x - 7 = 0$

On observation, the trinomial is not factorizable so we use the Completing the square method.

Step 1: Isolate the constant term by adding 7 to both sides

$2x^2 + 12x - 7+7 = 0+7\\2x^2 + 12x=7$

Step 2: Divide the equation all through by the coefficient of $x^2$ which is 2.

$x^2 + 6x=\frac{7}{2}$

Step 3: Divide the coefficient of x by 2, square it and add it to both sides.

Coefficient of x=6

Divided by 2=3

Square of 3= $3^2$

Therefore, we have:

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Step 5: Take the square root of both sides and solve for x

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2 years ago

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ladessa [460]

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j = 3k - 120
d = j

k + 20 = 3k - 120
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3 years ago

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hjlf

Answer:

Step-by-step explanation:

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2 years ago