Step-by-step explanation:
note that
sin²x = (1-cos²x)
LHS= cos²x - 2 sin²x
= cos²x - 2(1-cos²x)
= cos²x - 2 + 2cos²x
= 3cos²x - 2
or
cos²x = (1-sin²x)
LHS= cos²x - 2 sin²x
=1-sin²x - 2 sin²x
= 1-3sin²x
Answer: 3/11 = 0.27272727272727, -5/8 = 0.625
Step-by-step explanation:
If you take 0.98 and multiply by 2.5 you get 2.45 so there is no better deal. ☺
The scale of the map is equal to 250 miles per 1.7 feet. or 250m/1.7ft. set up as a fraction.
Divide 250 by 1.7 to get how many miles are equal to just 1 foot.
250/1.7 = 147.058824 miles per 1 foot
Multiply that times 3.06 feet (the distance between C and D on the map)
147.058824m/1ft x 3.06ft = 450m
The actual distance between City C and City D should be 450 miles.
So close! But instead of adding the multiplication sign after the number you need to add them before. Good job though! :)