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2 years ago

Which value for x makes the following equation TRUE? -2x - 4 = - 6

Mathematics

2 answers:

horrorfan [7]2 years ago

8 0

Answer:

Step-by-step explanation:

-2(1) = -2

then -2 - 4 = -6

-6 = -6

prisoha [69]2 years ago

3 0

Answer:

Step-by-step explanation:

Move all terms that don't contain x to the right side & solve.

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if i have 4 gallons 3 quarts - 3 quarts and 1 pint what would be the leftover gallons quarts and pint?

nataly862011 [7]

Step-by-step explanation:

3 gallons and 3.5 quarts

4 0

2 years ago

What is the area of the figure if x = 25 cm and y=20 cm?<br> Use 3.14 to approximate it.

Akimi4 [234]

The area of the circle is 6,358.5cm²

<h3>Area of the circle</h3>

The formula for calculating the area of a circle is expressed as;

A = πr²

r is the radius = x + y

r = 25 + 20 = 45cm

Substitute the given parameters into the formula to have:

A = 3.14(45)²

A = 6,358.5cm²

Hence the area of the circle is 6,358.5cm²

Learn more on area of a circle here; brainly.com/question/10645610

4 0

1 year ago

Show that √(1-cos A/1+cos A) =cosec A - cot A

Gennadij [26K]

Hi there!

$\sqrt{\frac{1-cosA}{1+cosA}} =$

We can begin by multiplying by its conjugate:

$\sqrt{\frac{1-cosA}{1+cosA}} * \sqrt{\frac{1+cosA}{1+cosA}} = \\\\\sqrt{\frac{(1-cosA)(1 + cosA)}{(1+cosA)(1 + cosA)}} =$

Simplify using the identity:

$1 - cos^2A = sin^2A$

$\sqrt{\frac{(1-cos^2A)}{(1+cosA)^2}} =\\\\\sqrt{\frac{(sin^2A)}{(1+cosA)^2}} =$

Take the square root of the expression:

${\frac{sinA}{1+cosA} =$

Multiply again by the conjugate to get a SINGLE term in the denominator:

${\frac{sinA}{1+cosA} * {\frac{1-cosA}{1-cosA} =\\$

Simplify:

${\frac{sinA(1-cosA)}{1-cos^2A} =$

Use the above trig identity one more:

${\frac{sinA(1-cosA)}{sin^2A} =$

Cancel out sinA:

${\frac{(1-cosA)}{sinA} =$

Split the fraction into two:

${\frac{1}{sinA} - \frac{cosA}{sinA} =$

Recall:

$1/sinA = cscA\\\\cosA/sinA = cotA$

Simplify:

$\frac{1}{sinA} + \frac{cosA}{sinA} = \boxed{cscA - cotA}$

5 0

1 year ago

A padlock has a four-digit code that includes digits from 0 to 9, inclusive. What is the probability that the code does not cons

Eduardwww [97]

Since there is no repetition allowed, there are 10 possibilities for the 1st digit, 9 for the 2nd, 8 for the 3rd, and 7 for the 4th. This gives a total of (10)(9)(8)(7) = 5040 four-digit codes.
For all odd digits to be used, there are 5 possibilities for the 1st digit (1,3,5,7,9), 4 for the 2nd, 3 for the 3rd, 2 for the 4th. This gives a total of (5)(4)(3)(2) = 120 codes that only use odd digits.
Therefore there are 5040 - 120 = 4920 codes that do not consist of all odd digits. The probability is 4920/5040 = 41/42.

4 0

2 years ago

Read 2 more answers

A sample of tritium-3 decayed to 94.5% of its original amount after a year.

Zolol [24]

(a) If $y(t)$ is the mass after $t$ days and $y(0) = A$ then $y(t) = Ae^{kt}.$

$y(1) = Ae^k = 0.945A \implies e^k = 0.945 \implies k = \ln 0.945$

$\text{Then } Ae^{(\ln 0.945)t} = \frac{1}{2}A\ \Leftrightarrow\ \ln e^{(\ln 0.945)t} = \ln \frac{1}{2}\ \Leftrightarrow\ ( \ln 0.945) t = \ln \frac{1}{2} \Leftrightarrow \\ \\
t = - \frac{\ln 5}{\ln 0.945} \approx 12.25 \text{ years}$

(b)
$Ae^{(\ln 0.945) t} = 0.20 A \ \Leftrightarrow\ (\ln 0.945) t \ln \frac{1}{5}\ \implies \\ \\
t = - \frac{\ln 5}{\ln 0.945} \approx 28.45\text{ years}$

3 0

2 years ago