The answer is 50%
if you list out the possibilities, you get
(H being heads, T being tails)
HHH <- 3 heads
HHT <- 2 heads
HTH <- 2 heads
HTT
THH <- 2 heads
THT
TTH
TTT
we counted 4 of them to have at least 2 heads out of the 8 possibilities
4/8 = 1/2 which is 50%
It is 7, C,
A= 1029
B=7203
It is valid.
The three angles must add up to 180. So, if one is more than 90, the other two have to be less than 90.
To simplify the equation. 2x - 4 + 3x, all you need to do is combine like terms, which are 2x and 3x. The resulting answer would be 5x - 4. Hope this helps and have a wonderful day!
