Answer:
0.48.
Step-by-step explanation:
There are 2 ways that a tail lands once:-
Tail + head or
head + tail.
Prob(Tail on one throw) = 0.4
Prob(Head on one throw) = 1 - 0.4 = 0.6.
Prob(Tail first then head) = 0.4 * 0.6 = 0.24
Head then tail has the same probability (0.6*0.4).
So the requred probability = 0.24 + 0.24
= 0.48.
(x-5)(x+3)=0
x^2+3x-5x-15=0
(x^2+3x) (-5x-15)
x(x+3) -5(x+3)
x-5=0 x+3=0
x=5 OR -3