cos(20) = sin(70)
note how 20+70 = 90
The general rule is that if x+y = 90, then cos(x) = sin(y). The rule works in reverse as well. Another way to phrase the rule is cos(x) = sin(90-x).
So,
Note: if the computer doesn't like the answer of "sin 70" then try "sin(70)" and see how that works out. It's also possible that the teacher wants the single numeric value of "70" in the first box rather than the "sine" part to go along with it. Though that would be strange and incorrect since cos(20) = 70 is a false statement.
The first is a. you can rewrite it
the second is d. the only common factor between 20 and 40 that can be taken out is the 4 which becomes a 2, but inside the square roots there is still a 5 and 10, which cannot be combined
the third is c.
the fourth is d.
add 3 to both sides
then square both sides
then divide both sides by 2, x=50
Answer:
D
Step-by-step explanation:
Answer:
6 × 5 × 5 square inches
Step-by-step explanation:
The area of one of the figure's 6 squares is the product of its side length, so is ...
5 × 5 square inches
The area of all 6 of those squares is 6 times this, or ...
6 × 5 × 5 square inches