Question

Solve for x: 4 over 5 x + 4 over 3 = 2x x = Write your answer as a fraction in simplest form. Use the "/" symbol for the fraction bar. (2 points)

Answer 1

Answer:

x = 10/9

Step-by-step explanation:

Solve for x:

(4 x)/5 + 4/3 = 2 x

Put each term in (4 x)/5 + 4/3 over the common denominator 15: (4 x)/5 + 4/3 = (12 x)/15 + 20/15:

(12 x)/15 + 20/15 = 2 x

(12 x)/15 + 20/15 = (12 x + 20)/15:

(12 x + 20)/15 = 2 x

Multiply both sides by 15:

(15 (12 x + 20))/15 = 15×2 x

(15 (12 x + 20))/15 = 15/15×(12 x + 20) = 12 x + 20:

12 x + 20 = 15×2 x

15×2 = 30:

12 x + 20 = 30 x

Subtract 30 x from both sides:

(12 x - 30 x) + 20 = 30 x - 30 x

12 x - 30 x = -18 x:

-18 x + 20 = 30 x - 30 x

30 x - 30 x = 0:

20 - 18 x = 0

Subtract 20 from both sides:

(20 - 20) - 18 x = -20

20 - 20 = 0:

-18 x = -20

Divide both sides of -18 x = -20 by -18:

(-18 x)/(-18) = (-20)/(-18)

(-18)/(-18) = 1:

x = (-20)/(-18)

The gcd of 20 and -18 is 2, so (-20)/(-18) = (-(2×10))/(2 (-9)) = 2/2×(-10)/(-9) = (-10)/(-9):

x = (-10)/(-9)

Multiply numerator and denominator of (-10)/(-9) by -1:

Answer: x = 10/9