Hello here is a solution :
Y = 9x - 5...the slope here is 9...a parallel line will have the same slope.
y = mx + b
slope(m) = 9
(5,-4)...x = 5 and y = -4
now we sub and solve for b, the y int
-4 = 9(5) + b
-4 = 45 + b
-4 - 45 = b
-49 = b
so ur parallel line is : y = 9x - 49
y = 9x - 5...slope is 9. A perpendicular line will have a negative reciprocal slope. All that means is " flip " the slope and change the sign. So the slope we need is -1/9.
y = mx + b
slope(m) = -1/9
(5,-4)...x = 5 and y = -4
now we sub and solve for b, the y int
-4 = -1/9(5) + b
-4 = -5/9 + b
-4 + 5/9 = b
-36/9 + 5/9 = b
- 31/9 = b
so ur perpendicular line is : y = -1/9x - 31/9
T=-1
sinA=sin(π/2-3A), A=2nπ+π/2-3A, 4A=2nπ+π/2, A=nπ/2+π/8 where n is an integer.
Also, π-A=2nπ+π/2-3A, 2A=2nπ-π/2, A=nπ-π/4.
The hard way:
cos3A=cos(2A+A)=cos(2A)cosA-sin(2A)sinA.
Let s=sinA and c=cosA, then s²+c²=1.
cos3A=(2c²-1)c-2c(1-c²)=c(4c²-3).
s=c(4c²-3) is the original equation.
Let t=tanA=s/c, then c²=1/(1+t²).
t=4c²-3=4/(1+t²)-3=(4-3-3t²)/(1+t²)=(1-3t²)/(1+t²).
So t+t³=1-3t², t³+3t²+t-1=0=(t+1)(t²+2t-1).
So t=-1 is a solution.
t²+2t-1=0 is a solution, t²+2t+1-1-1=0=(t+1)²-2, so t=-1+√2 and t=-1-√2 are solutions.
Therefore tanA=-1, -1+√2, -1-√2 are the three solutions from which:
A=-π/4, π/8, -3π/8 radians and these values +2πn where n is an integer.
Replacing π by 180° converts the solutions to degrees.
Answer:
PS=5.4
Step-by-step explanation:
The centroid divides each median in the ratio 2:1
If U is the centroid, then
We use ratio to obtain;
Cross multiply;
Expand;
Group similar terms;
x=1
PS=PU+US
PS=3.6+1+0.8
PS=3.6+1+0.8
PS=5.4
