Cos 157.5º=-cos (180º-157.5º)=-cos 22.5=-cos(45/2)
cos Ф/2=⁺₋√((1+cosФ)/2).
In this case 157.5º is in the second quadrant, therefore we use the following equation:
cos Ф/2=-√((1+cosФ)/2). (we will have a negative number)
cos 157.5º=-cos (45/2)=-√((1+cos 45º)/2)
=-√((1+√2/2)/2)
=-√((2+√2)/4)
=-√(2+√2) / 2 (≈-0.92387...)
Answer: cos 157.5º= -√(2+√2) / 2
Answer:
86
Step-by-step explanation:
y + 28 + 58 = 180
y + 86 = 180
y = 180 - 86
y = 94
x + y = 180
x + 94 = 180
x = 180 - 94
x = 86
compare to the correct answer on the picture. If not helped you can use a graph calculator and it should let you know wether or not you’re correct
Answer:
$6.4
Step-by-step explanation:
You just do 32 × .2 to give you the discount of 6.4
You multiple by .2 because 20% as a decimal is .2 ( you do 20% divided by 100 to give you .2)
Answer: b
Step-by-step explanation: the parallel proportionality theorem states that “if two or more parallel lines are intersected by two transversals, the parallel lines divide the transversals proportionally.” Therefore, you make a ratio and solve:
(4/2)=(6/x) and if you solve, x=3
now, 6+3=9, so 2x-11=9
if you solve for that, x=10