Answer:
B 41.4
Step-by-step explanation:
complete Pythagoras for general triangles :
c² = a² + b² - 2ab×cos(C)
with "c" being the side opposite of the angle C.
=>
8² = 10² + 12² - 2×10×12×cos(C)
64 = 244 - 240×cos(C)
240×cos(C) = 244 - 64 = 180
cos(C) = 180/240 = 18/24 = 3/4 = 0.75
C = 41.40962211... ≈ 41.4
Answer:
Angle R is an Angle
Step-by-step explanation:
This question has no photo or context
X equals 4 because 2 times 2 equals 4 and then 4 times 4 =16
First, let's cancel out the x by multiplying 2x + 18y = -9 by -2.
-2 ( 2x + 18y = -9) = -4x -36y = 18
Then, we combine the two equations.
-4x + 4x = 0
18y - 36y = -18y
-27 + 18 = -9
Our new equation is -18y = -9.
Now, divide both sides by -18.
-18y / -18 = y
-9/ -18 = 1/2
y = 1/2
We can plug in a value for y since y = 1/2 now.
Let's use 2x + 18y = -9
Plug in y.
2x + 18(1/2) = -9
2x + 9 = -9
Then, subtract 9 from both sides.
2x = -18
Divide by 2.
2x/2 = x
-18/2 = -9
x = -9
Lastly, we can plug in both x and y values to see it works.
2(-9) + 18(1/2) = -9
-18 + 9 = -9
Therefore, the values of x and y does work.
x = -9
y = 1/2
