What is the average rate of change from x = −3 to x = −4?<br> The parabola is open upward

(2,0) (4,5) write an equation that represents the line

Yuliya22 [10]

Answer:

the equation of the line in slope-intercept form would be y=5/2x-5

Step-by-step explanation:

hope this helped!! :D

4 0

2 years ago

A pharmacist has an 18% alcohol solution and a 40% alcohol solution. How much of each should he mix together to make 10 liters o

ladessa [460]

X = amount of the 18% solution

y = amount of the 40% solution

we know the 18% solution has only 18% of alcohol, the rest is maybe water or something, now, how many liters is 18%? well, 18% of anything is just (18/100) * anything, so, 18% of x is just (18/100) *x or 0.18x, and that's how many liters are there.

likewise, how many liters are there in the 40% solution? well, (40/100) * y, or 0.4y, that many.

we know the mixture has to yield 10 liters at 20% alcohol, how many liters of only alcohol is that? well, (20/100) * 10, or 2 liters.

$\bf \begin{array}{lccclll}
&\stackrel{liters}{amount}&\stackrel{alcohol~\%}{quantity}&\stackrel{liters}{alcohol}\\
&------&------&------\\
\textit{18\% solution}&x&0.18&0.18x\\
\textit{40\% solution}&y&0.40&0.4y\\
------&------&------&------\\
mixture&10&0.20&2
\end{array}$

$\bf \begin{cases}
x+y=10\implies \boxed{y}=10-x\\
0.18x+0.4y=2\\
----------\\
0.18x+0.4\left( \boxed{10-x} \right)=2
\end{cases}
\\\\\\
0.18x-0.4x+4=2\implies -0.22x=-2
\\\\\\
x=\cfrac{-2}{-0.22}\implies x=\cfrac{100}{11}\implies x=9\frac{1}{11}$

how much of the 40% solution? well y = 10 - x

3 0

3 years ago

Loris makes 20 bracelets in 50 minutes. Doris makes 44 bracelets in 2 hours. who makes more bracelets per hour. how many more?

Sedaia [141]

To do this, you'll have to get loris and doris to the same amount of time, we can already tell loris makes 40 bracelets in 100 minutes but we are still missing 20 minutes, so we got to do some math(Ofc we do its mathematics) if you divide 50 by 20 you'll get 2.5 which is how many minutes it takes to make a bracelet. So now we can go back to that missing 20 minutes, if you divide 20 by 2.5, you'll get 8. So in 2 hours loris makes 48 bracelets(20 + 20(50 hours each)=40 + 8(the missing 20 minutes) = 48) But here is the tricky part it says per an hour, so we need to reduce both by half, so loris makes 24 bracelets an hour and doris makes 22 bracelets an hour so loris makes 2 more bracelets and hour than doris... hope i've helped!

3 0

2 years ago

(PLEASE HELP)<br> Which value of x makes this equation true<br> -90=-100+x

riadik2000 [5.3K]

Answer:

-0.9

Step-by-step explanation:

-0.9 × 100 = -90

8 0

2 years ago

Read 2 more answers

Need help with number 2

salantis [7]

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7 0

3 years ago

What is the average rate of change from x = −3 to x = −4? The parabola is open upward