Answer:
(cos a cos b - sin a sin b)
Step-by-step explanation:
It's easy
Answer:
D
Step-by-step explanation:
We can rule out the second and third because the y intercept in those graphs are not 1
Now lets look at the point 2,5 on graph a
y=1/2x+1
so 5=1+1 but that is false
D is the answer by elimination
Answer: Y=mx+b
Step-by-step explanation:
M=slope
B= your y-coordinate
S = sisters ages
M =2S +7
M=13
13 = 2S+7
subtract 7 from each side
6 = 2S
divide by 2
3=S
sisters age is 3
Answer:
Step-by-step explanation:
Given
There are 52 cards in total
there are total of 13 pairs of same cards with each pair containing 4 cards
Probability of getting a pair or three of kind card=1-Probability of all three cards being different
Probability of selecting all three different cards can be find out by selecting a card from first 13 pairs and remaining 2 cards from remaining 12 pairs i.e.

for first card there are 52 options after choosing first card one pair is destroyed as we have to select different card .
For second card we have to select from remaining 12 pairs i.e. 48 cards and so on for third card.
Required Probability is 
