Question

Need help!!!! Please answer these equations and show your work. Thank you!!!

Answer 1

Problem 1.
Solve for x:
4 x + 3 = 19
Subtract 3 from both sides:
4 x + (3 - 3) = 19 - 3
3 - 3 = 0:
4 x = 19 - 3
19 - 3 = 16:
4 x = 16
Divide both sides of 4 x = 16 by 4:
(4 x)/4 = 16/4
4/4 = 1:
x = 16/4
The gcd of 16 and 4 is 4, so 16/4 = (4×4)/(4×1) = 4/4×4 = 4:
Answer:  x = 4

Problem 2. 

Solve for x:
(4 x)/3 + 5 = 17
Put each term in (4 x)/3 + 5 over the common denominator 3: (4 x)/3 + 5 = (4 x)/3 + 15/3:
(4 x)/3 + 15/3 = 17
(4 x)/3 + 15/3 = (4 x + 15)/3:
(4 x + 15)/3 = 17
Multiply both sides of (4 x + 15)/3 = 17 by 3:
(3 (4 x + 15))/3 = 3×17
(3 (4 x + 15))/3 = 3/3×(4 x + 15) = 4 x + 15:
4 x + 15 = 3×17
3×17 = 51:
4 x + 15 = 51
Subtract 15 from both sides:
4 x + (15 - 15) = 51 - 15
15 - 15 = 0:
4 x = 51 - 15
51 - 15 = 36:
4 x = 36
Divide both sides of 4 x = 36 by 4:
(4 x)/4 = 36/4
4/4 = 1:
x = 36/4
The gcd of 36 and 4 is 4, so 36/4 = (4×9)/(4×1) = 4/4×9 = 9:
Answer:  x = 9

Problem 3

Solve for x:
4 (6 - 2) x - 10 = 20
6 - 2 = 4:
4×4 x - 10 = 20
4×4 = 16:
16 x - 10 = 20
Add 10 to both sides:
16 x + (10 - 10) = 10 + 20
10 - 10 = 0:
16 x = 20 + 10
20 + 10 = 30:
16 x = 30
Divide both sides of 16 x = 30 by 16:
(16 x)/16 = 30/16
16/16 = 1:
x = 30/16
The gcd of 30 and 16 is 2, so 30/16 = (2×15)/(2×8) = 2/2×15/8 = 15/8:
Answer: x = 15/8

Problem 4

Solve for x:
4.3 x + 0.7 = 5
Subtract 0.7 from both sides:
4.3 x + (0.7 - 0.7) = 5 - 0.7
0.7 - 0.7 = 0:
4.3 x = 5 - 0.7
5 - 0.7 = 4.3:
4.3 x = 4.3
Divide both sides of 4.3 x = 4.3 by 4.3:
(4.3 x)/4.3 = 4.3/4.3
4.3/4.3 = 1:
x = 4.3/4.3
4.3/4.3 = 1:
Answer:  x = 1
As for the Real world question, I have no idea. Given are, $25 to turn on the electricity and $4/hr to run it.  What is she selling and for how much? I don't think there is a solution as not enough information is given.