Answer:
Step-by-step explanation:
If we choose chairs having odd number in the row
no of chairs from which selection is made = 10
no of chairs to be selected = 5
no of ways = 10C₅
similarly if we choose hairs having even numbers only ,
similar to above , no of ways
= 10C₅
Total no of ways
= 2 x 10C₅
= 2 x 10 x 9 x 8 x 7 x 6 / 5 x 4x3 x 2 x 1
= 504 .
Answer:
x=9 x=-1
Step-by-step explanation:
x²-8x-9=0 a=1 b=-8 c=-9
you have to use the quadratic formula to get the values.
Answer:
Estimation is a mental process of coming up with an answer that is relatively close, to allow decisions to be made. The types of estimation are quantity, computation and measurement.
An estimation strategy is simply coming up with a good estimate based on evidence and already known facts. Coming to a conclusion as close to the real answer as you can. It can also be called an educated guess.
Let :
T = Theresa age
H = her brother
We know :
T = H - 14
T + H = 35
Substitute T
H -14 + H = 35
2H - 14 = 35
2H = 49
H = 49/2 = 24.5
Since we know H = 24.5 we then can substitute it to either equation.
T = H - 14
T = 24.5 - 14
T = 10.5
Theresa is 10.5 years old
Her brother is 24.5 years old