Answer:
Step-by-step explanation:
1. 10² + 7² = x²
149 = x²
x = √149
2. x² + 19² = 21²
x² = 21² - 19² = 80
x = √80 = 4√5
3. x² + 16² = 27²
x² = 27² - 16² = 473
x = √473
4. 5.3² + 12.8² = x²
191.93 = x²
x = √191.93
5. 9² + 20² = x²
481 = x²
x = √481
6. 31 = x + 2√(19²-17²) = x + 2·6√2 = x + 12√2
x = 31 - 12√2
Answer:
npr= n! /(n-r) !
nCr= =(n r) = n! /r!(n-r)1
Step-by-step explanation:
Answer:
The sum of all angels for any triangle equals 180°
so we have a right triangle which means we have an angle equals 90° ,angle equals=56°.
step by step

so the angle tends to equal 34°.
Answer:
7 and 1/4 or 7.25
Step-by-step explanation:
28/4 = 7
1/4 = 0.25
7 + 0.25 = 7.25
Answer:
<h2>-3400</h2>
Step-by-step explanation:
In general, a geometric sequence is given by:
<h3>
a,
ar,
ar^2,
⋯,
ar^n−1 </h3>
In the sequence 20, - 40 , 80,…
First term, a1 = 20
Common ratio, r = - 40 ÷ 20 = - 2
The nth term is = 9th
Sum of finite geometric series : Sn= ( a1 - a1r^n ) / ( 1 - r)
S9 = ( 20 - 20 x (- 2)^9 ) / ( 1 - ( - 2) )
S9 = ( 20 - 20 x - 512 ) / ( 1 + 2 )
S9 = ( 20 - 10240<em> </em>) / ( 3 )
S9 = ( - 10220 ) / 3
<h3>S9 = - 3400 <u>Answer</u> </h3><h2>Hope it's help you.... ^_^❤️</h2>