The length of a rectangular room is 7.4m and it's width is 5.5m. Find the area of the room.

2/7x = 10 show work plz

Rashid [163]

Answer:

x = 35

Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :

2/7*x-(10)=0

2

Simplify —

7

2

(— • x) - 10 = 0

7

Subtracting a whole from a fraction

Rewrite the whole as a fraction using 7 as the denominator :

10 10 • 7

10 = —— = ——————

1 7

Adding up the two equivalent fractions

Add the two equivalent fractions which now have a common denominator

Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:

2x - (10 • 7) 2x - 70

————————————— = ———————

7 7

Pull out like factors :

2x - 70 = 2 • (x - 35)

2 • (x - 35)

———————————— = 0

7

When a fraction equals zero ...

Where a fraction equals zero, its numerator, the part which is above the fraction line, must equal zero.

Now,to get rid of the denominator, Tiger multiplys both sides of the equation by the denominator.

Here's how:

2•(x-35)

———————— • 7 = 0 • 7

7

Now, on the left hand side, the 7 cancels out the denominator, while, on the right hand side, zero times anything is still zero.

The equation now takes the shape :

2 • (x-35) = 0

Solve : 2 = 0

This equation has no solution.

A a non-zero constant never equals zero.

Solve : x-35 = 0

Add 35 to both sides of the equation :

x = 35

4 0

2 years ago

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Can someone please help me with this?

GrogVix [38]

The circumference of a circle with radius $r$ is $2\pi r$ . If the length of the radius is tripled, then the circumference becomes $2\pi(3r)=3\cdot2\pi r$ , which is just 3 times the original circle's circumference.

4 0

3 years ago

What is the answer to this?

dsp73

X=2 here’s why 90-32 is 58. 29x=58 then x is 2

4 0

1 year ago

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Tyler says that an<br> equivalent expression for 23 x 53 is 109.<br> Is he correct? Explain.

Sphinxa [80]

Answer:

Tyler is correct

Step-by-step explanation:

An expression is a representation of a value; for example, variables and/or numerals that appear alone or in combination with operators are expressions.

4 0

3 years ago

Read 2 more answers

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 + 1

Alex73 [517]

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:

$H(t)=70+120(\frac{1}{4})^t$

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

$H(0)=70+120(\frac{1}{4})^0\\H(0)=70+120\cdot 1\\H(0) = 70+120\\H(0)=190 \:\°F$

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

$H(1)=70+120(\frac{1}{4})^1\\H(1)=70+120(\frac{1}{4})\\H(1) = 70+30\\H(1)=100 \:\°F$

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

$H(2)=70+120(\frac{1}{4})^2\\H(2)=70+120(\frac{1}{16})\\H(2) = 70+\frac{15}{2} \\H(2)=77.5 \:\°F$

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

$85 = 70+120(\frac{1}{4})^t\\70+120\left(\frac{1}{4}\right)^t=85\\70+120\left(\frac{1}{4}\right)^t-70=85-70\\120\left(\frac{1}{4}\right)^t=15\\\frac{120\left(\frac{1}{4}\right)^t}{120}=\frac{15}{120}\\\left(\frac{1}{4}\right)^t=\frac{1}{8}$

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

$\ln \left(\left(\frac{1}{4}\right)^t\right)=\ln \left(\frac{1}{8}\right)$

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

$t\ln \left(\frac{1}{4}\right)=\ln \left(\frac{1}{8}\right)$

$t=\frac{\ln \left(\frac{1}{8}\right)}{\ln \left(\frac{1}{4}\right)}\\t=\frac{3}{2} = 1.5 \:hours$

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

$75=70+120\left(\frac{1}{4}\right)^t\\70+120\left(\frac{1}{4}\right)^t=75\\70+120\left(\frac{1}{4}\right)^t-70=75-70\\120\left(\frac{1}{4}\right)^t=5\\\left(\frac{1}{4}\right)^t=\frac{1}{24}$

$\ln \left(\left(\frac{1}{4}\right)^t\right)=\ln \left(\frac{1}{24}\right)\\t\ln \left(\frac{1}{4}\right)=\ln \left(\frac{1}{24}\right)\\t=\frac{\ln \left(24\right)}{2\ln \left(2\right)} \approx = 2.293 \:hours$

3 0

3 years ago