So legnt=l
width=w
l=-7+3w
l=3w-7
area=66
area=legnth times width or
area=lw
subisutte
area=lw
l=3w-7
66=(3w-7)(w)
66=3w^2-7w
subtrac 66 from both sides
0=3w^2-7w-66
factor
HOW TO
multiply 3 and -66=-198
find what 2 numbers add up to -7 and multiply to get -198
the numbers area 11 and -18
so
3w^2-18w+11w-66=0
factor
(3w^2-18w)+(11w-66)=0
(3w)(w-6)+(11)(w-6)=0
factor using distributive (ab+ac=a(b+c))
(3w+11)(w-6)=0
set them to zero
3w+11=0
subtract 11
3w=-11
legnths cannot be negative so we discard this
w-6=0
add 6
w=6
width=6
legnth=3w-7
length=3(6)-7
legnt=18-7
legnth=11
width=6
legnth=11
Every triangle equals 180 degrees, and we're trying to find the angle of DBA. So, we can identify DAB as a 90 degree angle to start. Then we can identify that ACB = ADB, meaning ADB is 30 degrees. With that information, we have this equation:
DBA = 180 - 90 - 30
DBA = 60
Answer:
The form of the sum of cubes identity is a³ + b³ = (a + b)(a² - ab + b²) ⇒ A
Step-by-step explanation:
To find the form of the sum of cubes identity ⇒ x³ + y³
- find the cube root of each one and add them in a small bracket ⇒ (x + y)
- square the first term in the small bracket and put it as the 1st term in a big bracket ⇒ (x² ....)
- put (-) after the 1st term ⇒ (x² - .....)
- multiply the 1st and 2nd term in the small bracket and put the product as the 2nd term in the big bracket ⇒ (x² - xy .....)
- square the 2nd term in the small bracket and add it to the terms of the big bracket ⇒ (x² - xy + y²)
Then the form of the sum of cubes identity is x³ + y³ = (x + y)(x² - xy + y²)
∵ a³ + b³ is a sum of two cubes
→ By using the same steps above
∵ ![\sqrt[3]{a^{3}}](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7Ba%5E%7B3%7D%7D)
= a and ![\sqrt[3]{b^{3}}](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7Bb%5E%7B3%7D%7D)
= b
∴ The small bracket is (a + b)
∵ Square a = a² and square b = b²
∵ a × b = ab
∴ The big bracket is (a² - ab + b²)
∴ The form of the sum of cubes identity is a³ + b³ = (a + b)(a² - ab + b²)
So basically all you have to do is find the area of one of the smaller semi circles by using the formula for the area of a circle (A=πr^2). You know that the length of the larger semi circle's radius is equivalent to 6 cm because the radius of the smaller ones are 3 cm, meaning the diameter would have to be 6 cm and in this case, the length of the smaller semi circles' diameters is equal to the radius of the big semi circle. Then you would find the area of the big semi circle again by using the area of a circle formula, but after getting the answer you would half it, obviously because it's a semi circle. Subtract the are of the smaller semi circle you found earlier from the answer you just got and that's it ;) (you wouldn't have to half the area since there are two smaller semi circles and 1/2 + 1/2 = 1 but u knew that)
Put simply, the answer would be about 88.2644 cm because circles.
<span>se
sen x = 3/5 eleva ao quadrado ambos os lados
sen² x = (3/5)²
Tem que partir da relação fundamental
sen²x + cos²x = 1
(3/5)² + cos² x = 1
cos² x = 1 - (3/5)² = 16/25
cos x = V(16/25 = 4/5
b ) tg x = sen x / cos x = 3/5 / 4/5 = 3/5 * 5/4 = 3/4
c) cotg x = cosx / sen x = 1 / tgx = 1/ (3/4 = 4/3
d) sec x = 1/ cos x = 1 / 4/5 = 5/4
e) cossec x = 1 / sen x = 1/ 3/5 = 5/3
se gostou , avalie
edson</span>edson <span>· 9 anos atrás</span>
