You do
10x30 + 10x2 + 5x30 +5x2
AB = 6 cm, AC = 12 cm, CD = ?
In triangle ABC, ∠CBA = 90°, therefore in triangle BCD ∠CBD = 90° also.
Since ∠BDC = 55°, ∠CBD = 90°, and there are 180 degrees in a triangle, we know ∠DCB = 180 - 55 - 90 = 35°
In order to find ∠BCA, use the law of sines:
sin(∠BCA)/BA = sin(∠CBA)/CA
sin(∠BCA)/6 cm = sin(90)/12 cm
sin(∠BCA) = 6*(1)/12 = 0.5
∠BCA = arcsin(0.5) = 30° or 150°
We know the sum of all angles in a triangle must be 180°, so we choose the value 30° for ∠BCA
Now add ∠BCA (30°) to ∠DCB = 35° to find ∠DCA.
∠DCA = 30 + 35 = 65°
Since triangle DCA has 180°, we know ∠CAD = 180 - ∠DCA - ∠ADC = 180 - 65 - 55 = 60°
In triangle DCA we now have all three angles and one side, so we can use the law of sines to find the length of DC.
12cm/sin(∠ADC) = DC/sin(∠DCA)
12cm/sin(55°) = DC/sin(60°)
DC = 12cm*sin(60°)/sin(55°)
DC = 12.686 cm
The ratio is 2:3 for the side lengths of the triangles.
so 6:9 is one side and 5:x would be the other side
2/3 of five is 3.33 and multiplying that by 2 gives you 6.67
Answer:
C. 238π cm^3.
Step-by-step explanation:
Surface area = 2 * area of the circular ends + area of the curved length
= 2π r^2 + 2π r* l
= 2 π 7^2 + 2π 7 * 10
= 98π + 140π
= 238π cm^3.
Answer:
1st question: M=22.62 while C=75.38
2nd question: M=.22 while C=1.97
Step-by-step explanation:
If a mirror costing x dollars is marked up 30%, then we have to find x such that 30%x+x is 98 dollars.
We are solving:
.3x+x=98
Combine like terms:
1.3x=98
Divide both sides by 1.3:
x=75.38
M=98-75.38=22.62
C=75.38
So M=22.62 while C=75.38.
If ream of paper cost x and is marked up 11%, then we have to find x such that 11%x+x is 2.19.
We are solving:
.11x+x=2.19
1.11x=2.19
x=1 97
M=2.19-1.97=.22
So M=.22 while C=1.97
