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MissTica
3 years ago
12

If sinA =3/5 and A+B =90 find cosB

Mathematics
1 answer:
-Dominant- [34]3 years ago
8 0

A+B=90^o\to B=90^o-A\\\\\cos B=\cos(90^o-A)=\cos90^o\cos A+\sin90^o\sin A\\\\=\cos A+1\cdot\dfrac{3}{5}=0+\dfrac{3}{5}=\dfrac{3}{5}\\\\\boxed{\cos B=\dfrac{3}{5}}

Used:\\\\\cos(x+y)=\cos x\cos y+\sin x\sin y\\\\\cos90^o=0,\ sin90^o=1

Other method:

Look at the picture.

\sin\theta=\dfrac{opposite}{hypotenuse}\\\\\sin A=\dfrac{3}{5}\to opposite=3\ and\ hypotenuse=5

\cos\theta=\dfrac{adjacent}{hypotenuse}\\\\adjacent=3\ and\ hypotenuse=5\to\cos B=\dfrac{3}{5}

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Vitek1552 [10]

Answer:

y=-2x-4

Step-by-step explanation:

<u>Perpendicular Bisector</u>

The bisector of a segment defined by points (x1,y1) and (x2,y2) must pass by the midpoint of the segment.

The midpoint (xm,ym) is calculated as follows:

\displaystyle x_m=\frac{x_1+x_2}{2}

\displaystyle y_m=\frac{y_1+y_2}{2}

The endpoints of the segment are (-3,-8) and (5,-4), thus the midpoint M is:

\displaystyle x_m=\frac{-3+5}{2}=1

\displaystyle y_m=\frac{-8-4}{2}=-6

Midpoint: M(1,-6)

Let's find the slope of the given segment. The slope can be calculated with the formula:

\displaystyle m_1=\frac{y_2-y_1}{x_2-x_1}

\displaystyle m_1=\frac{-4+8}{5+3}=\frac{1}{2}

If the bisector is also perpendicular, its slope m2 and the slope of the segment m1 must comply:

m_1.m_2=-1

Solving for m2:

\displaystyle m_2=-\frac{1}{m_1}=-\frac{1}{\frac{1}{2}}=-2

Once we have the slope -2 and the point through which our line must pass (1,-6), we compute the equation in its point-slope form:

y-y_o=m(x-x_o)

y-(-6)=-2(x-1)

Operating

y+6=-2(x-1)

y+6=-2x+2

Rearranging

\boxed{y=-2x-4}

8 0
4 years ago
your village community group is putting a new fence around the park .you offer to help and measure the distance around the park
makkiz [27]

Explanation:

Perimeter of the park

= 337 m

= 33700 cm

Length of each fence panel

= 550 cm

Number of fence panel required

= Perimeter of the park/Length of each fence panel

= 33700 cm/550 cm

= 33700/550

= 3370/55

= 674/11

= 61 3/11

So, we will need 61 3/11 fence panels.

P.S. — 61 3/11 means 61 whole and 3/11. I have attached its picture, so that you understand.

3 0
3 years ago
What is the measure of ABC?
Norma-Jean [14]

Answer:

C. 60

Step-by-step explanation:

You can take away 120 instantly because that angle is acute. This leaves you with A, B, and C. It's most certainly too big to be C. By this point you can look at it and draw a 90 degree angle in your mind and you can see that it looks about 2/3 of a 90 degree angle.

May I have brainliest please? :)

3 0
3 years ago
Geometry math question no Guessing and Please show work thank you
Sever21 [200]

Let us consider the triangles WKQ and MQK

WQ=KM (given) side

WK=MQ(given) side

KQ=KQ (common) side

so we have SSS congruency (option A)

6 0
3 years ago
From $25 to $35<br><br><br> The percent increase is
cestrela7 [59]

Answer:

40 percent

Step-by-step explanation:

Start by taking the difference of the two values:

35-25 = 10.

the $10 is how much the value increased by.

To get the percent that the $25 increased by, take 10/25 to get .4

This .4 can then be turned into a percentage when you multiply it by 100. = 40 percent.

You can check your answer by finding 40 percent of 25, which is 10.

4 0
3 years ago
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