The total amount paid by Oliver on this dinner is given by the cost of their lunch (275) plus the tax (12%) plus the tip (20%). So in order to calculate this value we first need to know how much was paid in tax and the tip, these calculations are shown bellow:

tax = 275*12% = 275*(12/100) = 33

tip = 275*20% = 275*(20/100) = 55

So the total amount paid was:

total = 275 + 33 + 55 = $363

Oliver paid a total of $363.

8 0

3 years ago

Hey can you please help me posted picture of question :)

otez555 [7]

Answer:
The solutions are -3 and -6

Explanation:
First we would need to put the equation in standard form which is:
ax² + bx + c = 0
This can be done as follows:
x² + 18 = -9x
x² + 9x + 18 = 0
By comparison, we would find that:
a = 1
b = 9
c = 18

Now, to get the roots, we would use the quadratic formula shown in the attached image.

By substitution, we would find that:
either x = $\frac{-9+ \sqrt{(9)^2-4(1)(18)} }{2(1)} = -3$

or x = $\frac{-9- \sqrt{(9)^2-4(1)(18)} }{2(1)} = -6$

Hope this helps :)