Answer:
Step-by-step explanation:
The sine of an angle is defined as the ratio between the opposite side and the hypotenuse of a given right-angled triangle;
sin x = ( opposite / hypotenuse)
The opposite side to the angle x is thus 1 unit while the hypotenuse is 3 units. We need to determine the adjacent side to the angle x. We use the Pythagoras theorem since we are dealing with right-angled triangle;
The adjacent side would be;
The cosine of an angle is given as;
cos x = (adjacent side / hypotenuse)
Therefore, the cos x would be;
Answer:
x = 8/7
Step-by-step explanation:
Step 1: Convert to math
7x - 5 = 3
Step 2: Solve for <em>x</em>
- Add to both sides: 7x = 8
- Divide both sides by 7: x = 8/7
"31-inch piece of steel is cut into three pieces"
Call the pieces a,b,c
a + b + c = 31
"second piece is twice as long as the first piece"
b = 2a
"third piece is one inch more than seven times the length of the first piece"
c = 1 + 7a
Ok, we have our equations, let's substitute the second and third into the first.
a + 2a + 1 + 7a = 31
10a + 1 = 31
10a = 30
a = 30/10 = 3
b = 2a = 6
c = 1 + 7a = 22
Check: 3 + 6 + 22 = 31, good
Answer: 3 inches, 6 inches, 22 inches
Answer:
<em>d = 3</em>
Step-by-step explanation:
Coordinate Plane
The image provided shows the four points given:
A=(2, 1), B=(5, 1), C=(7,2), D=(4,2).
It can be clearly seen the length of CD is just the difference of their x-coordinates:
CD = 7 - 4 = 3
We can also use the formula of the distance.
Given two points C(x,y) and D(w,z), the distance between them is:
d = 3
<h3>Answer:</h3>
±12 (two answers)
<h3>Explanation:</h3>
Suppose one root is <em>a</em>. Then the other root will be -3<em>a</em>. The product of the two roots is the ratio of the constant coefficient to the leading coefficient:
(<em>a</em>)(-3<em>a</em>) = -27/4
<em>a</em>² = -27/(4·(-3)) = 9/4
<em>a</em> = ±√(9/4) = ±3/2
Then the other root is
-3<em>a</em> = -3(±3/2) = ±9/2 . . . . . . the roots will have opposite signs
We know the opposite of the sum of these roots will be the ratio of the linear term coefficient to the leading coefficient: b/4, so ...
-(a + (-3a)) = b/4
2a = b/4
b = 8a = 8·(±3/2)
b = ±12
_____
<em>Check</em>
For b = 12, the equation factors as ...
4x² +12x -27 = (2x -3)(2x +9) = 0
It has roots -9/2 and +3/2, the ratio of which is -3.
For b = -12, the equation factors as ...
4x² -12x -27 = (2x +3)(2x -9) = 0
It has roots 9/2 and -3/2, the ratio of which is -3.
