Rule needed: i^2 = -1
Standard form a + bi
(3 + 2i)(7 - 5i) FOIL
3 * 7 = 21
3 * - 5i = - 15i
2i * 7 = 14i
2i * -5i = - 10i^2 = - 10 * -1 = 10
Putting it all back together.
31 - i
5/11 = 18/y
5 y = 18 · 11
5 y = 198
y = 198 : 5
y = 39.6
Answer:
x = 13.5
Step-by-step explanation:
direct variation
y = kx
substitute x and y to find k
8 = k*6
divide by 6
8/6 =k
4/3 = k
y = 4/3 x
now put in y =18
18 = 4/3 x
multiply by 3/4
18 * 3/4 = 3/4 * 4/3 x
54/4 = x
change to a decimal
13.5 =x
Answer:
a= c/2
b= (c/2)×√3
side b is the side with the 60 degree angle.
side a is the side with the 30 degree angle.
using the theorem that the side with the 60 degree × 2 = length of side c and the side with the 60 degree × √3 = b.
I get the following equations shown above.