The answer is -7.20 click on file for more details.
Answer:
a = 16
Step-by-step explanation:
To solve your question all you have to do is subtract 15 on both sides so,
15 - 15 + a = 31 - 15
Which will give you,
15 - 15 = 0
31 - 15 = 16
So,
a = 16
Hope this helps!!
Answer:
x = 3 ± sqrt(11)
Step-by-step explanation:
x^2 - 6x + 9 = 11
Recognizing that this is a perfect square trinomial
(x-3) ^2 =11
Taking the square root of each side
sqrt((x-3) ^2) = ± sqrt(11)
x-3 =± sqrt(11)
Add 3 to each side
x = 3 ± sqrt(11)
Answer: 20 child tickets were sold that day.
Step-by-step explanation:
Let x represent the number of child tickets that were sold that day.
Let y represent the number of adult tickets that were sold that day.
On Sunday, twice as many adult tickets as child tickets were sold. It means that
y = 2x
At the city museum, child admission is $6.30 and adult admission is $9.60. The total sales for that day was $510.00. It means that
6.3x + 9.6y = 510- - - - - - - - - - - -1
Substituting y = 2x into equation 1, it becomes
6.3x + 9.6 × 2x = 510
6.3x + 19.2x = 510
25.5x = 510
x = 510/25.5
x = 20
y = 2x = 2 × 20
y = 40
I think its D. because they get too used to the cells, so their DNA evolves to survive and resist the cells
