Answer:
1) ∠A=84°
2) ∠C=20°
Step-by-step explanation:
1)
First, find ∠C:
<em>(I'm assuming the exterior angle of 126° makes a straight line with ∠C)</em>
The angles on a straight line always add up to 180. Therefore:
∠C+126=180
∠C=180-126
∠C=54
Then find ∠B:
We also know that all the angles in a triangle add up to 180. Therefore:
∠A+∠B+∠C=180
∠A+∠B+54=180
∠A+∠B=126
<em>(we know ∠A=2(∠B))</em>
2(∠B)+∠B=126
3(∠B)=126
∠B=42
Now, find ∠A:
∠A=2(∠B)
∠A=2(42)
∠A=84°
2)
First, find ∠B:
<em>(Again, I'm assuming the exterior angle of 100° makes a straight line with ∠B)</em>
The angles on a straight line always add up to 180. Therefore:
∠B+100=180
∠B=180-100
∠B=80
Then find ∠A:
We also know that all the angles in a triangle add up to 180. Therefore:
∠A+∠B+∠C=180
∠A+80+∠C=180
∠A+∠C=100
<em>(we know ∠A=4(∠C))</em>
4(∠C)+∠C=100
5(∠C)=100
∠C=20°
Answer:
208 ft^3
Step-by-step explanation:
Let the plane through the 4 ft X 4ft square at the top of the figure break the figure into 2 boxes, one has dimensions (8-7) by 3 by 4 = 1ft X 3ft X 4ft, and the other has dimensions 7 by 7 by 4 = 7ft X 7ft X 4ft.
They have volumes of (1)(3)(4) = 12 ft^3, and (7)(7)(4) = 196 ft^3, respectively, so the total volume = 12 + 196 = 208 ft^3, the answer.
Answer:
G. ABD = 74
H. DBC = 206
I. XYW = 33.75
J. WYZ = 46.25
Step-by-step explanation:
For G and H: You have a straight line (ABC) with another line coming off of it, creating two angles (ABD and DBC). A straight line has an angle of 180 degrees. This means that the two angles from the straight line when combined will give you 180 degrees. Solve for x.
ABD + DBC = ABC
(1/2x + 20) + (2x - 10) = 180
1/2x + 20 + 2x - 10 = 180
5/2x + 10 = 180
5/2x = 170
x = 108
Now that you have x, you can solve for each angle.
ABD = 1/2x + 20
ABD = 1/2(108) + 20
ABD = 54 + 20
ABD = 74
DBC = 2x - 10
DBC = 2(108) - 10
DBC = 216 - 10
DBC = 206
For I and J: For these problems, you use the same concept as before. You have a right angle (XYZ) that has within it two other angles (XYW and WYZ). A right angle has 90 degrees. Combine the two unknown angles and set it equal to the right angle. Solve for x.
XYW + WYZ = XYZ
(1 1/4x - 10) + (3/4x + 20) = 90
1 1/4x - 10 + 3/4x + 20 = 90
2x + 20 = 90
2x = 70
x = 35
Plug x into the angle values and solve.
XYW = 1 1/4x - 10
XYW = 1 1/4(35) - 10
XYW = 43.75 - 10
XYW = 33.75
WYZ = 3/4x + 20
WYZ = 3/4(35) + 20
WYZ = 26.25 + 20
WYZ = 46.25
The product of two positive fractions are also less than one because you are multiplying a number which is already less than 1.
For example.
1/ 2 = is 50% of a whole.
When you multiply 1/2 by 1/2 you do not get the 100% of the whole because you are only getting 50% of the 50% of the whole, which in turn is equivalent to 25% of the whole.
1/2 * 1/2 = 1/4 of the whole.
The only time you can get a result of 1 and above where two fractions are less than 1 is when you perform addition of these fractions.
1/2 + 1/2 = 1 - ALL CREDITS GO TO @TASKMASTERS!
