just count how many there and and eliminate one by one
Answer:
7) a = 65; b = 50
8) c = 125; d = 55; e = 52
9) f = 105
Step-by-step explanation:
7)
a = 65
b + 130 = 180
b = 50
8)
c = 125
d + 125 = 180
d = 55
e = 52
9)
(180 - f) + 32 + (180 - 107) = 180
180 - f + 32 + 180 - 107 = 180
-f + 285 = 180
-f = -105
f = 105
Answer:
14 ways in all.
Step-by-step explanation:
A. If you use 2 quarters, you have to make the remaining 15� with either no
dimes or 1 dime and the rest in nickels.
That's 2 ways.
B. If you use 1 quarter, you have to make the remaining 40� with either no
dimes, 1 dime, 2 dimes, 3 dimes or 4 dimes and the rest, if any, in nickels.
That's 5 more ways.
C. If you don't use any quarters, you have to make the entire 65� with either
0, 1, 2, 3, 4, 5 or 6 dimes and the rest in nickels.
That's 7 more ways. 2+5+7 = 14 ways in all.
Answer:
5
Step-by-step explanation:
0+3+6+7+9=25
25/5=5
Consider the attached figure. If AB has length 1, then BC has length sin(15°) and CD (the altitude of triangle ABC) has length sin(15°)·cos(15°).
By the double angle formula for sin(α), ...
... sin(2α) = 2sin(α)cos(α)
Rearranging, this gives
... sin(α)·cos(α) = sin(2α)/2
We have
... CD = sin(15°)·cos(15°) = sin(2·15°)/2
... CD = sin(30°)/2 = (1/2)/2 = 1/4
That is, the altitude, CD, is 1/4 the hypotenuse, AB, of triangle ABC.