Answer:
Step-by-step explanation:
A rectangle had a length of 2x-7 and a width of 3x+8y
Perimeter P = 2(l + w)
P = 2(2x - 7 + 3x + 8y)
P = 2(5x + 8y - 7)
P= 10x + 16y - 14
You can not solve for a as all of the numbers are unknown
We'll use the following properties of sine and cosine to prove this:



Then it's just a matter of filling it in...
sin20sin40 * sin60sin80 = 1/2(cos20 - cos60) * 1/2 (cos20 - cos140) =
1/8( cos40 + 1 - cos160 - cos120 - cos40 - cos80 + cos80 + cos200) =
1/8(1 - cos160 - cos120 + cos200) =
1/8(1 - cos160 - cos120 + cos160) =
1/8(1 - cos120 ) = 1/8( 1 + 1/2 ) = 3/16
Answer:
4x+2
Step-by-step explanation:
(5x+4)-(x+2)=(5-1)*x+(4-2)=4x+2