Ask question

Ask question

All categories

3 years ago

15

The sides of an isosceles triangle are 5, 5, and 7. Find the measure of the vertex angle to the nearest degree.

2 answers:

allochka39001 [22]3 years ago

8 0

You can use the cosine law with the formula:
a^2 = b^2 + c^2 - 2*b*c*cosA
With a = 5, b = 5, c = 7,
7^2 = 5^2 + 5^2 - 2*5*7*cosA
49 = 25 + 25 - 70*cosA
70*cosA = 25 + 25 - 49
70*cosA = 1
cosA = 1/70
A = arccos (1/70) = 89.18 deg = 89 deg

olga2289 [7]3 years ago

7 0

Answerino:

89 degrees

You might be interested in

Please help due by 10:10!!!!!!!!!!

sertanlavr [38]

Answer:

yes

Step-by-step explanation:

distributing gets you 8x+ 12= 2x-2 +6x+14

8x+12=8x+12

when both sides are simplified, they are equal to each other. This means that there IS a value of x that would make the perimeters equal

not sure what the drop down answers are so hope this helps

4 0

3 years ago

the angle theta is located in quadrant 1 and cos of theta is 3/8. what is the value of sin of theta ?

ra1l [238]

Answer: sin of theta = (√55)/8

Step-by-step explanation:

Cosine is the x-value divided by the hypotenuse. We now know that since cosine is 3/8, that the hypotenuse is 8. In order to find the third side of the triangle (which would be the v-value), we must use Pythagorean theorem. The third side is square root 55. Sine equals the y-value divides by the hypotenuse. We know both of those values, so Sine of theta = square root of 55 divided by 8.

8 0

3 years ago

Find the sum of the first 90 terms of the sequence -4,-1,2,5,8

telo118 [61]

Answer:

1655

Step-by-step explanation:

Note the common difference d between consecutive terms of the sequence

d = - 1 - (- 4) = 2 - (- 1) = 5 - 2 = 8 - 5 = 3

This indicates the sequence is arithmetic with sum to n terms

$S_{n}$ = $\frac{n}{2}$ [ 2a₁ + (n - 1)d ]

Here a₁ = - 4, d = 3 and n = 90, thus

$S_{90}$ = $\frac{90}{2}$ [ (2 × - 4) + (89 × 3) ] = 45(- 8 + 267) = 45 × 259 = 1655

4 0

3 years ago

What is the area of a parallelogram whose bases are 9

Nady [450]

<em> </em><em>Base=9cm</em>

<em>height=3</em><em> </em><em>cm</em>

<em>Area</em><em> </em><em>of</em><em> </em><em>parallelogram=b*h</em>

<em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em>=</em><em>9</em><em>*</em><em>3</em>

<em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em>=</em><em>2</em><em>7</em><em>c</em><em>m</em><em>^</em><em>2</em><em>.</em>

<em>Hope</em><em> </em><em>this</em><em> </em><em>will</em><em> </em><em>help</em><em> </em><em>u</em><em>.</em><em>.</em><em>.</em><em>:</em><em>)</em>

6 0

4 years ago

1. Write a mixed number that is equivalent to 16

Bumek [7]

Answer:

15 4/4

Step-by-step explanation:

8 0

3 years ago