5a+4c-b<br><img src="https://tex.z-dn.net/?f=5a%20%2B%204c%20-%20b%20" id="TexFormula1" title="5a + 4c - b " alt="5a + 4c

Help! Exponential Equation WITHOUT CALCULATOR

ale4655 [162]

$
1.
(2^{x} -2^{-x})^{2} = 4^{2} \\ \\2^{2x}-2*2^{x}*2^{-x} + 2^{-2x} =4^{2} \\ \\2^{2x}-2*2^{x-x} + 2^{-2x} =4^{2} \\ \\ 2^{2x}+ 2^{-2x} - 2=16 \\ \\ 2^{2x}+ 2^{-2x} = 18

\\ \\ 2.( 2^{x})^{3} - (2^{-x}^) ^{3}= (2^{x} -2^{-x})(2^{2x}+2^{x}*2^{-x}+2^{-2x})
\\ \\ ( 2^{x})^{3} - (2^{-x}^)^{3}=(2^{x} -2^{-x})(2^{2x}+2^{-2x}+2^{x}*2^{-x})
\\ \\ ( 2^{x})^{3} - (2^{-x}^)^{3}=(2^{x} -2^{-x})(2^{2x}+2^{-2x}+1)
\\ \\ ( 2^{x})^{3} - (2^{-x}^)^{3}=(2^{x} -2^{-x})((2^{2x}+2^{-2x})+1)
$

$\\ \\ ( 2^{x})^{3} - (2^{-x})^{3} =(4)((18)+1)= 76
\\ \\ 2^{3x}-2^{-3x} =76
$

4 0

3 years ago

An equation of the horizontal line that passes through the point (-2,5)

Greeley [361]

Y=5 it's a horizontal lines so b in y=mx+b would have to be 5 and since it's horizonal, it doesn't have a slope so it's just y=5

8 0

3 years ago

Which measure is less than 435 inches?

Alex_Xolod [135]

435 inches = 36 1/4 ft.

So, the answer would be D) 12 ft. 3 in.

*Hope I helped :)*

7 0

3 years ago

If you buy six pens and one mechanical pencil, you'll get only $1 change from your $10 bill. but if you buy four pens and two me

xxTIMURxx [149]

Let p be the prize of a pen and m the prize of a mechanical pencils. If you buy six pens and one mechanical pencil, you spend 6p+m. We know that this equals 9, because you get 1$ change from a 10$ bill.

Similarly, if you buy four pens and two mechanical pencils, you spend 4p+2m, which is 8$, because now you get a $2 change. Put these equation together in a system:

$\begin{cases} 6p+m=9\\4p+2m=8\end{cases}$

Now, if you multiply the first equation by 2, the system becomes

$\begin{cases} 12p+2m=18\\4p+2m=8\end{cases}$

Subtract the second equation from the first:

$12p+2m - (4p+2m) = 18-8 \iff 8p = 10 \iff p = \dfrac{10}{8} = 1.25$

Plug this value into the first equation to get

$6p+m=9 \iff 6\cdot 1.25 +m = 9 \iff 7.5 +m=9 \iff m = 9-7.5 = 1.5$

7 0

2 years ago

Kate took out a subsidized Stafford loan worth $9,710 to pay for college. The interest rate on the loan was 5.9%, compounded mo

NikAS [45]

<span>If Kate took out a loan of $9,710 and it took her 5 years to pay off she would have to pay 60 months of interest. Given that, the interest rate of 5.9% would of been $572.89 the first month. Use this information to find the answer.

Thank you for posting your question here at brainly. I hope the answer will help you. Feel free to ask more questions.
</span>

3 0

2 years ago