Answer:
4 hours
Step-by-step explanation:
For three visits, the electrician earned $40 × 3 = $120 in "per-visit" charges. For working x hours, he earned 20x in "per-hour" charges. The total of these came to 50x:
120 +20x = 50x
120 = 30x . . . . . . . . subtract 20x
4 = x . . . . . . . . . . . . . divide by 30
The electrician worked 4 hours that day.
Answer:
Step-by-step explanation:
2x = 3y + 1/2
standard : Ax + By = C
2x = 3y + 1/2....multiply everything by 2 to get rid of the fractions
4x = 6y + 1 ....subtract 6y from both sides
4x - 6y = 1 <==
slope intercept : y = mx + b
2x = 3y + 1/2....subtract 1/2 from both sides
2x - 1/2 = 3y....divide everything by 3
2/3x - 1/6 = y...rearrange
y = 2/3x - 1/6 <===
Answer:
27x^3 - 54x^2 + 36x - 8
Step-by-step explanation:
(3x - 2)^3
= (3x - 2) (3x - 2) (3x - 2)
= 27x^3 - 54x^2 + 36x - 8
Hope this helps :)
Let me know if there are any mistakes!!
Answer:
x= -13
y= -28
Step-by-step explanation:
To find the two numbers, write a system of equations with x as one number and y as another:
x-y=15
5x=2y-9
Use substitution to substitute one equation into another. Then solve for the variable.
x=15+y into 5x=2y-9
becomes
5(15+y) = 2y-9
75+5y = 2y- 9
75+3y= -9
3y = -84
y= -28
To find x, substitute y= -28 into one equation.
x - (-28) = 15
x+28 =15
x = 15-28
x=-13
