We are given here the individual costs of DVD and CD as well as the total sales and the number of items sold on one day. To solve the number of DVDs and CDs sold each, we devise two independent linear equations:
(1) x + y = 39
(2) 4x + 7y = 204
x- number of DVDs; y - number of CDs
solving, x= 23 DVDs
Answer:
=64 %
Step-by-step explanation:
The percentage decrease is found by
Percent decrease = (original - new)/ original * 100 percent
The original price is 25
The new price is 9
Percent decrease = (25-9)/25 * 100%
=16/25 * 100%
=64 %
4. What you want to do is first find the tan ratio, because tangent is opposite / adjacent, which you can use to find x.
So tan(52) = 1.28 ish. So we know that x/18 = 1.28.
Then multiply both sides by 18.
x / 18 * 18 = 1.28 * 18
x = about 23.
5. Now, you can use the pythagorean's theorem, a^2 + b^2 = c^2.
Just input all values.
18 ^ 2 + 23 ^ 2 = c ^ 2
324 + 529 = c ^ 2
853 = c^2
square root of 853 = c
x = 29.2 ish
6. In this case, use cosine, or adjacent / hypotenuse.
cos(16) = 0.96 ish
so that means 24/x = 0.96
Then basically,
24 / 0.96 = x
x = 25
So x = 25
Then you can use the Pythagorean's Theorem again. I'm not going to go as in depth.
a ^ 2 + b ^ 2 = c ^ 2
24 ^ 2 + b ^ 2 = 25 ^ 2
576 + b ^ 2 = 625
b ^ 2 = 49
b = 7
8. Use tan here. opposite/adjacent Again, not going as in depth.
tan(55) = 1.43 ish
1.43 = Y / 22
1.42 * 22 = Y
Y = 31.24 ish
Length of MN:
31.24 ^ 2 + 22 ^ 2 = c ^ 2
976ish + 484 = c ^ 2
1460 = c ^ 2
x = 38.2 ish
10. Use cosine.
cos(63) = about 0.45
Adjacent / hypotenuse
3 / x = 0.45
3 / 0.45= x
x = 6.67
And then pythagorean's Theorem.
6.67 ^ 2 = 3 ^ 2 + b ^ 2
44.5 = 9 + b ^ 2
35.5 = b^2
b = about 6
A. 63
B. 171
C.25
D. 12
This should be right I believe?<span />
