Answer:
A
Step-by-step explanation:
Recall that for a quadratic equation of the form:
The number of solutions it has can be determined using its discriminant:
Where:
- If the discriminant is positive, we have two real solutions.
- If the discriminant is negative, we have no real solutions.
- And if the discriminant is zero, we have exactly one solution.
We have the equation:
Thus, <em>a</em> = 2, <em>b</em> = 5, and <em>c</em> = -<em>k</em>.
In order for the equation to have exactly one distinct solution, the discriminant must equal zero. Hence:
Substitute:
Solve for <em>k</em>. Simplify:
Solve:
Thus, our answer is indeed A.
Cost of the spa treatment = $42
Percentage of sales tax = 6%
Percentage of tips = 20%
Normally the tips amount is calculated before adding sales tax.
Then
Amount of tips given = (20/100) * 42
= (1/5) * 42
= 8.40 dollars
Amount of sales tax taken = (6/100) * 42
= 252/100
= 2.52 dollars
Then
The total amount spent for spa treatment = (42 + 8.40 + 2.52) dollars
= 52.92 dollars
So we can see that $52.92 has been spent in total for spa treatment and this amount includes a sales tax of $2.52 and a tip of $8.40.
(3x+2) (x-7)
FOIL
first 3x*x = 3x^2
outer 3x*-7 = -21x
inner = 2*x = 2x
last 2*-7 = -14
add them together = 3x^2 -21x+2x -14
combine like terms 3x^2 -19x -14
The answer is r and s because it’s in the same plane.
