X^2 - 8x-9=0
D = b^2- 4*a*c = 64- 4* (-9) = 64+36=100 =10^2
X1 = (8-10)/2 = -1
X2= (8+10)/2= 9
7 classes because $32 -$25 = 7 (where $25 is for one month, and the 7 is how much is left over of the total and 1 class = $1 dollar)
Step-by-step explanation:

Answer:
111°
Step-by-step explanation:
Let the centre of the circle be C
mRQ=157 (marked)
The angle at the centre of a circle standing on an arc is twice any angle at the circumference, standing on the same arc. So <SCR=2(SQR)=2(46)=92. mSR=<SCR=92
All the arc measure add up to 360 so:
mSQ+mRQ+mSR=360
mSQ+157+92=360
mSQ=360-249=111
Knowing that logarithm functions and exponential functions are inverse to each other, the procees to convert a logarithmic equation to its equivalent is to perform all the operations to set an equation of the typ:

,
then invert to show it equivalent form:

.
With that you have solved the equation for x.