Answer:
C. 40.2°
Step-by-step explanation:
Cosine rule (real handy to remember): c² = a² + b² - 2·a·b·cos(γ)
If you don't know this yet, look it up but in short: c, a and b are the lengths of the sides of the triangle, the angle opposite side a is called α, for b it is β and for c it is γ. That's the convention I've always used anyway, you can call them whatever of course. Anyhow:
c² = a² + b² - 2·a·b·cos(γ)
⇒ |AC|² = |AB|²+|BC|²-2·|AB|·|BC|·cos(∠B)
⇒ |AC|²-|AB|²-|BC|² = -2·|AB|·|BC|·cos(∠B)
⇒ ( |AC|²-|AB|²-|BC|² ) / ( -2·|AB|·|BC| ) = cos(∠B)
⇒ ∠B = arccos( ( |AC|²-|AB|²-|BC|² ) / ( -2·|AB|·|BC| ) )
= arccos( ( 11²-16²-16² ) / ( -2·16·16 ) )
= 40.21101958°
≈ 40.2°
Answer:
x=1337/528
Step-by-step explanation:
-314x-214x=-1312-25
-528x=-1337
x=1337/528
Answer:
y = x^2 +6x+8
Step-by-step explanation:
First find the zeros, -4 ,-2
y =a (x - -4) (x - -2)
y = a(x+4)(x+2)
Then it is multiplied by a constant so pick a point on the curve and solve for the constant
We will use (0,8)
8 = a(0+4)(0+2)
8 = a(8)
a =1
y = (x+4)(x+2)
Writing in standard form
FOIL
y = x^2 +2x+4x+8
y = x^2 +6x+8
You put in the number for x. Here are the answers across
6 6 6
18 9 18
30 12 30
The answer to this question, is y=-2x
