377,225 views
16 votes
16 votes
B is between A and C. AB = 3x + 1, BC = 2x, and AC = 21. Find X.

User Emerald
by
2.6k points

2 Answers

22 votes
22 votes

Answer:


x = 4

Explanation:


AB + BC = AC \\ (3x +1) +(2x) = 21 \\ 3x +1 +2x = 21 \\ (3 +2)x +1 = 21 \\ 5x +1 = 21 \\ 5x +1 -1 = 21 -1 \\ 5x = 20 \\ (5x)/(5) = (20)/(5) \\ x = 4

User Stanislav Berkov
by
2.9k points
18 votes
18 votes


\\ \ast\sf\hookrightarrow AB+BC=AC


\\ \ast\sf\hookrightarrow 3x+1+2x=21


\\ \ast\sf\hookrightarrow 5x+1=21


\\ \ast\sf\hookrightarrow 5x=21-1


\\ \ast\sf\hookrightarrow 5x=20


\\ \ast\sf\hookrightarrow x=(20)/(5)


\\ \ast\sf\hookrightarrow x=4

B is between A and C. AB = 3x + 1, BC = 2x, and AC = 21. Find X.-example-1
User Shaun Barney
by
2.8k points
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