Which equation is true

Answers

Answer 1

Answer: The answer would be letter B.
9x2-25=(3x+5)(3x-5)

Answer 2

Answer: second one: 9x2 - 25 = (3x- 5)(3x+5)

Related Questions

I AM IN A TEST AND I NEED THE ANSWER SOON!!! PLEASEE!!!THANK YOU SO MUCH!!
Plz i need help on this
8 pencils and one eraser cost $1.35 and 6 pencils and one eraser cost $1.05. How much does one pencil cost?
9.87 x 10^7 - 2.5 x 10^6answer in scientific notation
Find the area of shaded region

The temperature, H, in °F, of a cup of coffee t hours after it is set out to cool is given by the following equation. H = 70 + 120(1/4)t (a) What is the coffee's temperature initially (that is, at time t = 0)? 190 °F What is the coffee's temperature after 1 hour? 100 °F What is the coffee's temperature after 2 hours? (Round your answer to one decimal place.) 2 °F (b) How long does it take the coffee to cool down to 85°F? (Round your answer to three decimal places.) 5 hr How long does it take the coffee to cool down to 75°F? (Round your answer to three decimal places.) 5 hr

Answers

Answer:

The temperature a t = 0 is 190 °F

The temperature a t = 1 is 100 °F

The temperature a t = 2 is 77.5 °F

It takes 1.5 hours to take the coffee to cool down to 85°F

It takes 2.293 hours to take the coffee to cool down to 75°F

Step-by-step explanation:

We know that the temperature in °F, of a cup of coffee t hours after it is set out to cool is given by the following equation:

$H(t)=70+120((1)/(4))^t$

a) To find the temperature a t = 0 you need to replace the time in the equation:

$H(0)=70+120((1)/(4))^0\nH(0)=70+120\cdot 1\nH(0) = 70+120\nH(0)=190 \:\°F$

b) To find the temperature after 1 hour you need to:

$H(1)=70+120((1)/(4))^1\nH(1)=70+120((1)/(4))\nH(1) = 70+30\nH(1)=100 \:\°F$

c) To find the temperature after 2 hours you need to:

$H(2)=70+120((1)/(4))^2\nH(2)=70+120((1)/(16))\nH(2) = 70+(15)/(2) \nH(2)=77.5 \:\°F$

d) To find the time to take the coffee to cool down $85 \:\°F$ , you need to:

$85 = 70+120((1)/(4))^t\n70+120\left((1)/(4)\right)^t=85\n70+120\left((1)/(4)\right)^t-70=85-70\n120\left((1)/(4)\right)^t=15\n(120\left((1)/(4)\right)^t)/(120)=(15)/(120)\n\left((1)/(4)\right)^t=(1)/(8)$

$\mathrm{If\:}f\left(x\right)=g\left(x\right)\mathrm{,\:then\:}\ln \left(f\left(x\right)\right)=\ln \left(g\left(x\right)\right)$

$\ln \left(\left((1)/(4)\right)^t\right)=\ln \left((1)/(8)\right)$

$\mathrm{Apply\:log\:rule}=\log _a\left(x^b\right)=b\cdot \log _a\left(x\right)$

$t\ln \left((1)/(4)\right)=\ln \left((1)/(8)\right)$

$t=(\ln \left((1)/(8)\right))/(\ln \left((1)/(4)\right))\nt=(3)/(2) = 1.5 \:hours$

e) To find the time to take the coffee to cool down $75 \:\°F$ , you need to:

$75=70+120\left((1)/(4)\right)^t\n70+120\left((1)/(4)\right)^t=75\n70+120\left((1)/(4)\right)^t-70=75-70\n120\left((1)/(4)\right)^t=5\n\left((1)/(4)\right)^t=(1)/(24)$

$\ln \left(\left((1)/(4)\right)^t\right)=\ln \left((1)/(24)\right)\nt\ln \left((1)/(4)\right)=\ln \left((1)/(24)\right)\nt=(\ln \left(24\right))/(2\ln \left(2\right)) \approx = 2.293 \:hours$

Please answer this correctly without making mistakes

Answers

Answer: 4.3 mi

Step-by-step explanation:

From Oxford, getting to Kingswood takes 7.5mi, and getting to Norwood takes 11.8mi. Thus, simply do 11.8-7.5 to get 4.3mi.

Hope it helps <3

a new recipe calls for 1/3 cups sugar and you have 2 1/3 cups in the pantry if you have unlimited supplies of the other ingredients how many recipes could you make? PLS HELP

Answers

Answer:

7 recipes could be made with $2(1)/(3)$ cups of sugar.

Step-by-step explanation:

Quantity of sugar required for a recipe $=(1)/(3)$ cups

Quantity of sugar required in a pantry $=2(1)/(3)$ cups

Here,

$2(1)/(3)=(7)/(3)$

So,

Quantity of sugar required in a pantry $=(7)/(3)$ cups

Number of recipes that could be made $=((7)/(3) )/((1)/(3) ) =7$

Therefore, 7 recipes could be made with $2(1)/(3)$ cups of sugar.

Gabrielle is 5 years older than Mikhail. The sum of their ages is 53 . What is Mikhail's age?

Answers

Let, the Age of Mikhail = x
Age of Gabrielle = x + 5

It is given that, x + x+ 5 = 53
2x = 53 - 5
x = 48/2
x = 24

In short, Mikhail is 24 years old.

Hope this helps!

A missile uses an internal computer clock to measure time in tenths of a second. The missile guidance system needs the time from launch, in seconds, in order to calculate its distance from the launch site. It obtains this by multiplying the computer clock time by 0.1. So, for example, a reading of 50 tenths of a second is 5 seconds. For one particular missile system, the conversion factor of 0.1 is stored in 8 bits as the binary number 0.000110012.The missile’s internal computer clock shows 200 tenths of a second. Convert this to seconds using your result from Part (i) of this question. Do not round your answer. The missile guidance system now records that it has travelled for this number of seconds.

Answers

Using proportions, it is found that the missile's internal computer clock is of 20 seconds.

According to the information given, this question can be solved by proportions, using a rule of three.

50 tenths of a second is equivalent to 5 seconds, and we want to find the equivalent to 200 tenths of a second, thus, the rule of three is:

50 tenths - 5 seconds

200 tenths - x seconds

Applying cross multiplication:

$50x = 5(200)$

$50x = 1000$

$x = (1000)/(50)$

$x = 20$

The missile's internal computer clock is of 20 seconds.

A similar problem is given at brainly.com/question/24372153

Y+z+ 2; use y=-6, and z = 5

Answers

When y = -6 and z = 5, the value of the expression y + z + 2 is 1.

To calculate the expression y + z + 2 when y = -6 and z = 5, you simply substitute these values into the expression and perform the arithmetic operations:

y + z + 2 = (-6) + (5) + 2

Now, perform the addition:

(-6) + (5) + 2 = -1 + 2 = 1

So, when y = -6 and z = 5, the value of the expression y + z + 2 is 1.

for such more question on expression

brainly.com/question/4344214

#SPJ2

Answer:

Step-by-step explanation:

y + z + 2

first you have to replace the variables with the numbers

This is your equation now.