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How do u do this?
4-5x=2x+25

User Cammace
by
3.2k points

2 Answers

12 votes

Answer:

x = -3

Explanation:

Solve for x:

-5 x + 4 = 2 x + 25

Subtract 2 x from both sides:

(-5 x - 2 x) + 4 = (2 x - 2 x) + 25

-5 x - 2 x = -7 x:

-7 x + 4 = (2 x - 2 x) + 25

2 x - 2 x = 0:

-7 x + 4 = 25

Subtract 4 from both sides:

(4 - 4) - 7 x = 25 - 4

4 - 4 = 0:

-7 x = 25 - 4

25 - 4 = 21:

-7 x = 21

Divide both sides of -7 x = 21 by -7:

(-7 x)/(-7) = 21/(-7)

(-7)/(-7) = 1:

x = 21/(-7)

The gcd of 21 and -7 is 7, so 21/(-7) = (7×3)/(7 (-1)) = 7/7×3/(-1) = 3/(-1):

x = 3/(-1)

Multiply numerator and denominator of 3/(-1) by -1:

Answer: x = -3

User FunkySayu
by
4.2k points
10 votes

Answer:

x = -3

Explanation:

=> 4-5x=2x+25

=> -5x-2x= 25-4

=> -7x = 21

=> x = -21/7

=> x = -3

User Yasar
by
4.4k points