Answer:
Cross multiplication is the method used to determine whether or not a proportion is true.
Explanation:
If you know one ratio in a proportion, you can use that information to find values in the other equivalent ratio.
Cross multiplication is the method used to determine whether or not a proportion is TRUE.
For example, if a bowl of fruit contains 10 oranges and 8 lemons, then the ratio of oranges to lemons is 10 is to 8 (that is, 10 : 8 ), which is equivalent to the ratio 5:4).
Answer: x=(7√6)/2
Step-by-step explanation:
To find x, we would have to find the hypotenuse of the 45-45-90 triangle. First, we would have to find the hypotenuse by using the 30-60-90 triangle on top to find it.
For a 30-60-90 triangle, the hypotenuse is 2x in length. the x is the same in all sides. All you would have to do is to plug it in. The leg opposite of 60° is x√3 in length. the leg opposite of 30° is x in length.
Since we know that 7 is opposite of the 30° angle, we know that x is 7. Across fron 60° is the hypotenuse of the 45-45-90 triangle. That leg is x√3. We plug in x=7 and get 7√3.
The hypotenuse of the 45-45-90 triangle is x√2 and the legs are both x. We can set 7√3 equal to x√2 to find x of the missing side.
7√3=x√2 [divide both sides by √2]
x=(7√6)/2
Now, we know x=(7√6)/2.
-x^2 -2x-6
Multiply everything by negative one to make X positive
X^2+2x+6
Use quadratic formula
-2+-sq rt of 2^2-4(1)(6) / 2
-2+-sqrt of -20 /2
-2+ 2i/2. -2-2i/2
-2+i. -2-i
Answer:
- 0.944
Step-by-step explanation:
We know that,
cos 3A = 4 cos³A - 3 cos A (formula)
So,
If cos A = 0.4,
cos 3A = 4 cos³A - 3 cos A
cos 3A = 4 × (0.4)³ - 3 × (0.4)
cos 3A = 4 × 0.064 - 1.2
cos 3A = - 0.944
Hope it helps ⚜