True
<span>Cos(A+B)=CosACosB-SinASinB
therefore Cos(A+A)= CosACosA - SinASinA
= Cos^2A - Sin^2A</span>
Answer:
$40
Step-by-step explanation:
x is the original price of the gift
(10% of x) is the value of the discount
(10% of x) = 10/100 . x = 0.1 x
0.1 x is the value of the discount
x - (10% of x) is what was paid, after the discount
x - 0.1 x = 0.9 x
0.9 x is what was paid
4 children paid $9/each
4 times $9 = $36
$36 is the total amount that was paid by the children
$36 = 0.9 x
$36 / 0.9 = x
x = $36 / 0.9 = 360 / 9
x = 40
;-)
$0.30x=y should be the answer because there is a 30cent fee for every day and x represents how many days it's kept therefore you would add 30 cents for every day it's kept so it's valid to say $0.30x=y becaue the 30 cents times the total of days it's kept = y (the toatl)
Perdenicular lines I think
Answer:
1.C (I’m not sure). 2.C 3. 30 4.Yes 5.C
Step-by-step explanation:
your welcome 1. Is logic 2. You set them equal and get 5 3. It’s a 17 15 8 so 15*2=30 4. They are all true. 5. That squared is that