It is a right agn have a good day
Answer:
578.3 ft²
Step-by-step explanation:
slope lengths are
L = √(11² + (13/2)²) = √163.25
A = (13 + 2√163.25)(15) = 578.307970...
Answer:
11 yrs
Step-by-step explanation:
Mean = sum of ages/number of ages
Let the age of the seventh girl be A
Given the addition of the age of the seventh girl will make the mean of the ages be 13,
So,
13 = 17+8+12+15+15+13+A/7
Add up the ages
13 = 80 + A /7
Cross multiply
80 + A = 13 x 7
80 + A = 91
Subtract 80 from both sides to isolate A
80 - 80 + A = 91 - 80
A = 11
The age of the seventh girl is 11
Answer:
1 + cosa sina
Step-by-step explanation:

cos³a - sin³a ← is a difference of cubes and factors in general as
a³ - b³ = (a - b)(a² + ab + b²) , then
cos³a - sin³a
= (cosa - sina )(cos²a + cosa sina + sin²a)
= (cosa - sina)(1 + cosa sina) [ sin²a + cos²a = 1 ]
Then

=
← cancel (cosa - sina) on numerator/ denominator
= 1 + cosa sina