Step-by-step explanation:
x=y+9
substitute
3(y+9)+8y=-6
3y+27+8y= -6
13y = -6 -27
13y= -33
y = -33/13
x = -33/13 + 9
X = 20
Isolate the variable by dividing each side by factors that don't contain the variable.
x
=
20
Answer:
1. y=2x-2
Because the slope is 2 over 1. and the y-intercept is at -2.
2. I think is y=1/5x-2
Answer: the service charge per hour for premium services is $5.5
the service charge per hour for regular services is $3
Step-by-step explanation:
Let x represent the service charge per hour for premium services.
Let y represent the service charge per hour for regular services.
One customer was charged $38 after spending 2 h in premium areas and 9 regular hours. It means that
2x + 9y = 38- - - - - - - - - - - 1
Another customer spent 3 h in premium areas and 6 regular hours and was charged $34.50. It means that
3x + 6y = 34.5- - - - - - - - - - -2
We would eliminate x by multiplying equation 1 by 3 and equation 2 by 2. It becomes
6x + 27y = 114
6x + 12y = 69
Subtracting, it becomes
15y = 45
y = 45/15
y = 3
Substituting y = 3 into equation 1, it becomes
2x + 9 × 3 = 38
2x + 27 = 38
2x = 38 - 27 = 11
x = 11/2 = 5.5
Answer:
-7
Step-by-step explanation:
x+3y
Let x =2 and y = -3
2 +3(-3)
2 -9
-7