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LuckyWell [14K]

2 years ago

6

the half-life of bismuth-210 is 5 days. if 25 grams of bismuth-210 are present initially, how much will remain after 10 days?

1 answer:

Jet001 [13]2 years ago

3 0

10 days is twice the half-life. After 5 days, can expect $\dfrac{25}2$ grams to remain; after another 5 days, you'd be left with $\dfrac{25}4$ grams.

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The function f(x)=5(2)^x was replaced with f(x)+k , resulting in the function graphed below. what is the value of k?

xxTIMURxx [149]

Since adding a constant to a function simply moved the graph upwards by that amount, solve f(x) for any value and see how much the graph given is different from that value of y...the simplest way in this case may be to simply find f(0) which is:

5*2^0=5

Clearly the graph at x=0 is at y=-2 so we can see that k is:

5+k=-2 so

k=-7

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3 years ago

a bread recipe calls for ⅓ cup of butter you want to make ½ of a batch. how much butter do you need?

Reil [10]

Answer:

1/6

Step-by-step explanation:

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2 years ago

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2 years ago

When you are trying to find the endpoint when given the midpoint and one point, what would the new formula be? Manipulate the fo

MariettaO [177]

Answer:

$(x_2,y_2) = (2x_m - x_1 ,2y_m - y_1 )$

Step-by-step explanation:

Given

$\left(\frac{x_1+\:x_2}{2},\:\:\frac{y_{1\:}+y_2}{2}\right)\:=\:\left(x_m,\:y_m\right)$

Required

Determine x2, y2

Start by splitting the expression

$x_m = \left(\frac{x_1+\:x_2}{2})$ and $y_m = (\frac{y_{1\:}+y_2}{2})$

Solving for x2 in $x_m = \left(\frac{x_1+\:x_2}{2})$

Multiply through by 2

$2 * x_m = \frac{x_1 + x_2}{2} * 2$

$2x_m = x_1 + x_2$

Make x2 the subject;

$x_2 = 2x_m - x_1$

Similarly:

$y_m = (\frac{y_{1\:}+y_2}{2})$

Multiply through by 2

$2 * y_m = \frac{y_1 + y_2}{2} * 2$

$2y_m = y_1 + y_2$

Make y2 the subject;

$y_2 = 2y_m - y_1$

Hence:

$(x_2,y_2) = (2x_m - x_1 ,2y_m - y_1 )$

7 0

2 years ago

ABC is isosceles.<br>m < a = 3x + 40 and m < c = x + 50<br>what is m < a ??

il63 [147K]

Answer:

55°

Step-by-step explanation:

<u>It is assumed the angles A and C are congruent:</u>

3x + 40 = x + 50
3x - x = 50 - 40
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m∠A = 3*5 + 40 = 55°

7 0

2 years ago

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