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3 years ago

What number must you add to complete the square x^2-16=23

Mathematics

2 answers:

Yanka [14]3 years ago

6 0

Answer:

6,24

Step-by-step explanation:

6,24^2-16= 22,9376 -> 23

Kobotan [32]3 years ago

4 0

For this case we must complete squares:

$x ^ 2-16x = 23$

We add the square of half the coefficient of the term "x",

$(\frac {b} {2a}) ^ 2$ on both sides of the equation:

$x ^ 2-16x + (\frac {-16} {2 (1)}) ^ 2 = 23 + (\frac {-16} {2 (1)}) ^ 2\\x ^ 2-16x + (- 8) ^ 2 = 23 + 64$

According to the perfect square trinomial we have:

$(a + b) ^ 2 = a ^2 + 2ab + b ^ 2$

Rewriting the expression we have:

$a = x\\b = -8\\(x-8) ^ 2 = 23 + 64\\(x-8) ^ 2 = 87$

ANswer:

$(x-8) ^ 2 = 87$

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Which point would be a solution to the system of linear inequalities ?

brilliants [131]

Answer:

(12,-6)

Step-by-step explanation:

we have

$y\leq \frac{4}{3}x+5$ ----> inequality A

$y\geq -\frac{5}{2}x+5$ ---> inequality B

we know that

If a ordered pair is a solution of the system of inequalities, then the ordered pair must satisfy both inequalities (makes true both inequalities)

Verify each point

Substitute the value of x and the value of y of each ordered pair in the inequality A and in the inequality B

case 1) (0,-1)

Inequality A

$-1\leq \frac{4}{3}(0)+5$

$-1\leq5$ ----> is true

Inequality B

$-1\geq -\frac{5}{2}(0)+5$

$-1\geq 5$ ----> is not true

therefore

The ordered pair is not a solution of the system

case 2) (0,3)

Inequality A

$3\leq \frac{4}{3}(0)+5$

$3\leq5$ ----> is true

Inequality B

$3\geq -\frac{5}{2}(0)+5$

$3\geq 5$ ----> is not true

therefore

The ordered pair is not a solution of the system

case 3) (-6,-6)

Inequality A

$-6\leq \frac{4}{3}(-6)+5$

$-6\leq-3$ ----> is true

Inequality B

$-6\geq -\frac{5}{2}(-6)+5$

$-6\geq 20$ ----> is not true

therefore

The ordered pair is not a solution of the system

case 4) (12,-6)

Inequality A

$-6\leq \frac{4}{3}(12)+5$

$-6\leq21$ ----> is true

Inequality B

$-6\geq -\frac{5}{2}(12)+5$

$-6\geq -25$ ----> is true

therefore

The ordered pair is a solution of the system (makes true both inequalities)

8 0

3 years ago

Arabella's password consists of 1 letter followed by two digits. What is the probability of correctly guessing Arabella's passwo

Alchen [17]

The answer is 1/2600

Hope this helps

6 0

3 years ago

A box has a volume of 308 cm cubed. Its height is 4 cm greater than its length. Its length is 3 cm greater than its width. What

kifflom [539]

Answer:

4 cm.

Step-by-step explanation:

Given:

A box has a volume of 308 cm cubed.

Its height is 4 cm greater than its length.

Its length is 3 cm greater than its width.

Question asked:

What is the width of the box?

Solution:

Let width = $x\ cm$

Length = $x+3\ cm$

Height = $x+3+4=x+7\ cm$

As we know:

$Volume\ of\ box=length\times width\times height$

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