2 because the equation can be reduced to: 8.0 x 10^4.
Step-by-step explanation:
Given that,
A meal plan lets students buy $20 meal cards.
Each meal card lasts about 8 days.
Let us assume that y denotes number of days for a 20 dollar meal card i.e. $20 every 8 days.
Let x = number of $ for another day.
So,


Hence, this is the required equation.
(a ± b)² = a² ± 2ab + b² . . . . . . . (signs match)
The middle term is twice the product of the roots of the other two terms. This tells you the terms of the binomial are the square roots of the end terms.
The sign in the binomial will match the sign of the "2ab" term. The order of terms in the binomial doesn't matter. (a±b)² = (b±a)² when signs match.
Answer: The first day the author reaches 100 days is on day 16.
To solve this problem, you could use a graphing calculator to graph the given equation. Then, determine when this line crosses 100. It crosses when x = 15.539. Therefore, we would have to round up to 16 so it is at least 100.
You could use the quadratic equation to solve: 100 = x^2 -12x + 45
Either you will get 16. If you use the quadratic formula, make sure to only use the positive answer.
The answer is D. 4x7+5=33 8x7+5=61. Hope it helps