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3 years ago

Which Expression is equivalent to -7 - (-2.5)

Mathematics

1 answer:

Verizon [17]3 years ago

6 0

Answer:

Step-by-step explanation:-4.5

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Complete the table for the given rule. Rule: y = 6x-4 Please help

d1i1m1o1n [39]

y = 6x - 4

Substitute the given x values to solve for y.

x = 1:

y = 6(1) - 4

y = 6 - 4

y = 2

1 = 2

x = 3:

y = 6(3) - 4

y = 18 - 4

y = 14

3 = 14

x = 10:

y = 6(10) - 4

y = 60 - 4

y = 56

10 = 56

x y

1 2

3 14

10 56

5 0

3 years ago

What is 80%of 1,60 will mark brainliest

cluponka [151]

Answer:

Step-by-step explanation:

Converte 80% into a decimal (devide it by 100) = 0.8

Then multiply 0.8 by 1.60 = 1.28 (final result)

4 0

2 years ago

A bacteria culture starts with 12,000 bacteria and the number doubles every 50 minutes.

Vlada [557]

Answer:

a) $y=12000(2)^{\frac{t}{50}}$

b) Approx. 27,569 bacteria

c) About 103 minutes

Step-by-step explanation:

This will follow exponential modelling with form of equation shown below:

$y=Ab^{\frac{t}{n}}$

Where

A is the initial amount (here, 12000)

b is the growth factor (double, so growth factor is "2")

n is the number of minutes in which it doubles, so n = 50

Substituting, we get our formula:

$y=Ab^{\frac{t}{n}}\\y=12000(2)^{\frac{t}{50}}$

To get number of bacteria after 1 hour, we have to plug in the time into "t" of the formula we wrote earlier.

Remember, t is in minutes, so

1 hour = 60 minutes

t = 60

Substituting, we get:

$y=12000(2)^{\frac{t}{50}}\\y=12000(2)^{\frac{60}{50}}\\y=12000(2)^{\frac{6}{5}}\\y=27,568.76$

The number of bacteria after 1 hour would approximate be 27,569 bacteria

To get TIME to go to 50,000 bacteria, we will substitute 50,000 into "y" of the equation and solve the equation using natural logarithms to get t. Shown below:

$y=12000(2)^{\frac{t}{50}}\\50,000=12,000(2)^{\frac{t}{50}}\\4.17=2^{\frac{t}{50}}\\Ln(4.17)=Ln(2^{\frac{t}{50}})\\Ln(4.17)=\frac{t}{50}*Ln(2)\\\frac{t}{50}=\frac{Ln(4.17)}{Ln(2)}\\\frac{t}{50}=2.06\\t=103$

After about 103 minutes, there will be 50,000 bacteria

4 0

3 years ago

What is the slope of the line that passes through the points (-2,7) and (2,-5) in simplest form ?

creativ13 [48]

Its $m=\dfrac{\Delta y}{\Delta x}=\dfrac{7-(-5)}{-2-2}=\dfrac{12}{-4}=\boxed{-3}$ .

Hope this helps.

6 0

3 years ago

Find the roots. 2x 2 + 7x - 15 =0

Reika [66]

So you always want to pull out the gcf first but since there isn't one, we can move on.
so we can make an acb chart which is multiplying the a value and the c value and find factors that of that product that will equal the b value.
a value is 2
c value is -15
b value is 7
-30 factors to equal 7 = 10, -3
10 - 3 = 7
so the factors 10 and -3 work.
so now you make 2 separate parenthesis with one of the factors and one x. and it should be set equal to 0.
(x+10)(x-3) = 0
now solve for x in each separate parenthesis.
x = -10
x = 3
those r the roots
hope this helps

4 0

3 years ago

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