Step-by-step explanation:
to find height :
draw a height from A to CD
height = (13) 2 - 5) 2 = 12 Cm
area = 10+20 /2 X 12= 180 cm 2
Answer:
Expanded, the answer would be 10b + 40
Step-by-step explanation:
Just multiply 8 to 2b and 8
Answer:
B)-20
Step-by-step explanation:
Answer: 42/13
Step-by-step explanation: Multiply everything by 7 to eliminate the fraction:
k+ 21 - 14k = -21
Isolate the variable:
k - 14k = -21-21
13k= -42
divide the sides by -13.
42/13
Answer:
x = 3π/4, 5π/4
Step-by-step explanation:
cos(x+2π) = -√2/2, [0,2π]
cos(x)cos(2π)-sin(x)sin(2π) = -√2/2
cos(x) = -√2/2
x = 3π/4, 5π/4
Remember that the cosine function is periodic, so cos(θ+2π)=cos(θ).