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3 years ago

Will give brainiest if correct A. 69.1 B. 20.9 C. 22.4 D. 67.6

Mathematics

2 answers:

Free_Kalibri [48]3 years ago

8 0

Using sin law;

sin A/ a = sinB/ b

where A = C or 90 degrees; a = 21
B = ? , b = 8

solving for b;
sin(90) / 21 = sin(B) / 8 ; B = 22.39 degrees

Total angle of triangle = 180

180 - 90 - 22.39 = x
x = 67.607 degrees

Anna35 [415]3 years ago

4 0

I think it's D. But I'm not sure if my math was correct

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Dayton picked 56 lemons. Zaiden picked 8 lemons. How many times as many lemons did Dayton pick as zaiden?

Dmitrij [34]

Answer:

7 times as many lemons

Step-by-step explanation:

56/8 = 7

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3 years ago

Explain how to use a pattern to find 35.6 ÷10 to the second power

Ad libitum [116K]

10 to the 2nd power only means 10x10=100
35.6/100=0.256
35.6/10x10=0.256

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3 years ago

Read 2 more answers

What greatest three digit number whose hundreds is two less than its ones digit

kodGreya [7K]

Answer:

799

Step-by-step explanation:

Let x = the hundreds digit

Let y = the ones digit

x = y-2

We want to maximize x and y. The both have to be single digit numbers

Rewriting this

x+2 =y

The largest x can be is 7 if y is a single digit

x is 7 and y is 9

We can pick the tens digit. Make it as big as possible to make out number as large as possible

799

4 0

3 years ago

Which expression is equivalent to 174 :

Archy [21]

174 is equal to 174 if thats what the last one means

8 0

3 years ago

The sum of first three terms of a finite geometric series is -7/10 and their product is -1/125. [Hint: Use a/r, a, and ar to rep

Alchen [17]

Ooh, fun

geometric sequences can be represented as
$a_n=a(r)^{n-1}$
so the first 3 terms are
$a_1=a$
$a_2=a(r)$
$a_2=a(r)^2$

the sum is -7/10
$\frac{-7}{10}=a+ar+ar^2$
and their product is -1/125
$\frac{-1}{125}=(a)(ar)(ar^2)=a^3r^3=(ar)^3$

from the 2nd equation we can take the cube root of both sides to get
$\frac{-1}{5}=ar$
note that a=ar/r and ar²=(ar)r
so now rewrite 1st equation as
$\frac{-7}{10}=\frac{ar}{r}+ar+(ar)r$
subsituting -1/5 for ar
$\frac{-7}{10}=\frac{\frac{-1}{5}}{r}+\frac{-1}{5}+(\frac{-1}{5})r$
which simplifies to
$\frac{-7}{10}=\frac{-1}{5r}+\frac{-1}{5}+\frac{-r}{5}$
multiply both sides by 10r
-7r=-2-2r-2r²
add (2r²+2r+2) to both sides
2r²-5r+2=0
solve using quadratic formula
for $ax^2+bx+c=0$
$x=\frac{-b \pm \sqrt{b^2-4ac}}{2a}$
so
for 2r²-5r+2=0
a=2
b=-5
c=2

$r=\frac{-(-5) \pm \sqrt{(-5)^2-4(2)(2)}}{2(2)}$
$r=\frac{5 \pm \sqrt{25-16}}{4}$
$r=\frac{5 \pm \sqrt{9}}{4}$
$r=\frac{5 \pm 3}{4}$
so
$r=\frac{5+3}{4}=\frac{8}{4}=2$ or $r=\frac{5-3}{4}=\frac{2}{4}=\frac{1}{2}$

use them to solve for the value of a
$\frac{-1}{5}=ar$
$\frac{-1}{5r}=a$
try for r=2 and 1/2
$a=\frac{-1}{10}$ or $a=\frac{-2}{5}$

test each
for a=-1/10 and r=2
a+ar+ar²= $\frac{-1}{10}+\frac{-2}{10}+\frac{-4}{10}=\frac{-7}{10}$
it works

for a=-2/5 and r=1/2
a+ar+ar²= $\frac{-2}{5}+\frac{-1}{5}+\frac{-1}{10}=\frac{-7}{10}$
it works

both have the same terms but one is simplified

the 3 numbers are $\frac{-2}{5}$ , $\frac{-1}{5}$ , and $\frac{-1}{10}$

6 0

3 years ago