First calculate the hourly rate, which is the difference of cleaning 2 and 1 rooms:
175-125=50
then calculate the initial value by subtracting the hourly rate from the "1 room" cost:
125-50=75
The initial cost might be something like driving to the place (which is only necessary once), while the rate covers work time or cleaning utensils used.
Normally, we could add exponents.
however, that only is possible when the bases are the same
recall what exponents mean
12³=12*12*12
so we cannot add exponents for 12³*11³ because that means 12*12*12*11*11*11
it would not equal 12⁶ or 11⁶
or you could refer to the rule

notice when x=x then we can add the bases
fun fact below
we can reverse a previous exponential rule like this
since

then

therefor

we can't add the exponents because the bases are not the same
Step-by-step explanation:
Correct option is
D
a
=0,b
=0
The condition for ax+by+c=0 to be a linear eqaution in two variables is
a
=0,b
=0
If you factor the equation you can see what the solutions are. Two factor a quadratic of the form ax^2+bx+c, find two values which satisfy two conditions...
jk=ac=-15 and j+k=b=-2 so j and k must be -5 and 3 so the factors are:
(x-5)(x+3)
So the other solution is x=5