Question

Which equation, when solved, gives 8 for the value of X?

A. 5/2x +7/2=3/4x+14


B. 5/4x-9=3/2x-12


C. 5/4x-2=3/2x-4


D. 5/2x-7=3/4x+14

Answer 1

Option C: (5/4)x - 2 = (3/2)x - 4

Explanation:

A) (5/2)x + (7/2) = (3/4)x + 14

Multiply through by 4 to get;

10x + 14 = 3x + 56

10x - 3x = 56 - 14

7x = 42

x = 42/7

x = 6

B) (5/4)x - 9 = (3/2)x - 12

Multiply through by 4 to get;

5x - 36 = 6x - 48

6x - 5x = 48 - 36

x = 12

C) (5/4)x - 2 = (3/2)x - 4

Multiply through by 4 to get;

5x - 8 = 6x - 16

6x - 5x = 16 - 8

x = 8

D) (5/2)x - 7 = (3/4)x + 14

Multiply through by 4 to get;

10x - 28 = 3x + 56

10x - 3x = 56 + 28

7x = 84

x = 84/7

x = 12