Answer is 9.
-3x^2 + 243 = 0
Bring 243 to the right.
-3x^2 = -243
Divide by -3.
x^2 = 243/3 = 81
Tak the square root of both sides.
x = 81^1/2 = 9.
Answer: There are 18 quarters and 3 dimes in $4.80
Step-by-step explanation:

Step-by-step explanation:
The vertex form of the equation for a parabola is given by

where (h, k) are the coordinates of the parabola's vertex. Since the vertex is at (1, -6), we can write the equation as

Also, since the parabola passes through (4, -7), we can use this to find the value for a:

or

Therefore, the equation of the parabola is

Answer:
y = 2x - 81
Step-by-step explanation:
20*5%= 20* 0.05=1 , and 1 year= 365 days, so 1 *355=$355 in one year I think, but I’m not sure how to use the formula