Answer:
X=-1
Y=1
Solve using Elimination.
Step-by-step explanation:
Multiply the second equation by 7.
The two equations are now:
7x+6y=-1
-7x +14y=21
Combine the two equations
7x and -7x cancel each other out, 14y+6y is 20y, and 21 - 1 is 20.
The equation is now
20y=20, divide 20 on both sides to get Y=1.
Now, substitute 1 as Y in the second equation for -x+2(1)=3
-x+2=3, can be simplified, by subtracting 2 from both sides. Giving us
-x=1.
Divide both sides by -1 for X=-1
Final answers being X=-1, Y=1
Hope this helps! Let me know if you have further questions!
Answer:
Joey is 2 years old and Martine is 16 years old.
Step-by-step explanation:
Answer:
Step-by-step explanation:
500
Answer:
Step-by-step explanation:
cos (x/2)=cos x+1
cos (x/2)=2cos ²(x/2)
2 cos²(x/2)-cos (x/2)=0
cos (x/2)[2 cos (x/2)-1]=0
cos (x/2)=0=cos π/2,cos (3π/2)=cos (2nπ+π/2),cos(2nπ+3π/2)
x/2=2nπ+π/2,2nπ+3π/2
x=4nπ+π,4nπ+3π
n=0,1,2,...
x=π,3π
or x=180°,540°,...
180°∈[0,360]
so x=180°
or
2cos(x/2)-1=0
cos (x/2)=1/2=cos60,cos (360-60)=cos 60,cos 300=cos (360n+60),cos (360n+300)
x/2=360n+60,360n+300
x=720n+120,720n+300
n=0,1,2,...
x=120,300,840,1020,...
only 120° and 300° ∈[0,360°]
Hence x=120°,180°,300°
Answer:
c = 60
Step-by-step explanation:
A triangle = 180 degrees
180-(15+105)=c
c=60
