hectictar

Don bought 0 apples.

He bought 12 appels but 0 apples.

Unless Don is being sneaky and he bought apples without telling anyone about it.

I can show you a couple different "ways" of doing it. (They all accomplish the same thing though.)

$x - \frac{80}{100} = 90 \\~\\ x=90+\frac{80}{100} \\~\\ x=\frac{454}{5}=90.8$

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$x - \frac{64}{100} = 72 \\~\\ x-0.64=72 \\~\\ x=72+0.64=72.64$

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$x - 15\% = 146.54 \\~\\ x - 0.15 = 146.54 \\~\\ x = 146.54 + 0.15 =146.69$

$\frac{x}{7} = \frac{30}{100} \\~\\ x = (7)(\frac{30}{100}) \\~\\ x = 210/100 = 2.1$

Law of Sines:

$\frac{\sin A}{a} = \frac{sin B}{b} = \frac{\sin C}{c}$

Plug in what you know.

$\frac{\sin56}{49} = \frac{\sin C}{58} \\~\\ \frac{58\sin56}{49} = \sin C \\~\\ \arcsin({\frac{58\sin56}{49}}) = C \\~\\ C \approx 78.905^{\circ}$

So since we know that there are 180º in every triangle,

180 ≈ 56 + 78.905 + B

B ≈ 180 - 56 - 78.905

B ≈ 45.095º

I just realized that you might have meant:

$\sqrt{\frac{270.4}{10}} \\~\\ = \sqrt{\frac{676}{25}} \\~\\ = \frac{\sqrt{676}}{\sqrt{25}} \\~\\ = \frac{26}{5}$

Which comes out to a nice even 5.2, so that is possibly what you meant.

$\frac{40}{x} = \frac{75}{100} \\~\\ 40 = \frac{75x}{100} \\~\\ 4000 = 75x \\~\\ 53\frac{1}{3} = x$

5y + 8 > 4y - 3

Subtract 8 from both sides.

5y + 8 - 8 > 4y - 3 - 8

5y > 4y - 11

Subtract 4y from both sides.

5y - 4y > 4y - 4y - 11

1y > -11

y > -11

h(z) = 2z² - 5z + 7

To find h(3c), replace each z with 3c.

h(3c) = 2(3c)² - 5(3c) + 7

Now just simplify.

h(3c) = 2(9c²) - 5(3c) + 7

h(3c) = 18c² - 15c + 7

Are these examples of what you mean?

34.375 = 34 and 375/1000 = 34 and 3/8

2.86 = 2 and 86/100 = 2 and 43/50

5.348 = 5 and 348/1000 = 5 and 87/250

Using the change of base formula:

$\log_{2}(x/y) = \frac{log_{10}(x/y)}{\log_{10}2} = 3 \\~\\ \log_{10}(x/y)=3(\log_{10}2) \\~\\ \log_{10}(x/y)=\log_{10}(2^3) \\~\\ x/y = 2^3 \\~\\ x/y = 8$

So x = 8y    and     y = x/8

I don't know what Guest did, but I'm pretty sure y can't be zero because that would make a zero in the denominator and that would mean that it doesn't equal 3, it would just not be a true statement.