Answer:
16.2
Step-by-step explanation:
The angle internal to the triangle at B is the supplement of the one shown, so is 65°. That is equal to the angle internal to the triangle at D. Since the vertical angles at C are congruent, the two triangles are similar by the AA theorem.
Corresponding sides of similar triangles are proportional, so we can write the proportion shown in the attachment:
BC/FC = DC/AC
BC = FC(DC/AC) = 21.6(7.2/9.6)
BC = 16.2 . . . . matches the first choice
Answer:
<u>A. Nicholas will have to pay less using plan A</u>
<u>B. He will pay US$ 4 less than plan B</u>
Step-by-step explanation:
Let's compare how much Nicholas will pay on internet service in Plan A and plan B, after using it 16 hours and 40 minutes.
Plan A
Up to 10 hours = US$ 6
Every subsequent 1/2 hour: $1
10 hours + 14 (1/2 hour)
<u>Nicholas will pay 6 + 14 * 1 = US$ 20</u>
Plan B
Up to 12 hours = US$ 4
Every subsequent 1/2 hour: $2
12 hours + 10 (1/2 hour)
<u>Nicholas will pay 4 + 2 * 10 = 24</u>
Answer:
x = 61
Step-by-step explanation:
Left hand triangle containing 1 angle of 74
Label the other angle opposite the marked side also as 74
Find the third angle. Call it y.
y + 74 + 74 = 180 Combine like terms
y + 148 = 180 Subtract 148 from both sides.
y = 180 - 148
y = 32
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Now work with the triangle on the right.
label the angle making up the right angle = z
32 + z = 90 These two angles are complementary = 90
32 - 32 + z = 90 - 32 Subtract 32 from both sides
z = 58 Use 58 wherever you see z
x + x + z = 180 Substitute
2x + 58 = 180 Subtract 58 from both sides
2x = 122 Divide by 2
x = 61
If you separate the triangles, you'll notice that both are literally the same triangle because all angles are the same.
First distribute the 2 through the parenthses on the right side.
So we have y - 4 = 2x + 8.
In slope-intercept form, the y is by itself on the left side.
So we add 4 to isolate the y on the left to get y = 2x + 12.
So in slope-intercept form, our equation is y = 2x + 12.
