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AM = 5x - 2 and MB = 2x + 19, Find the length of AB

User Vishnu T S
by
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1 Answer

3 votes

Answer:

The answer would be: -0.01

Explanation:

1) State what is given

AM = 5x -2 and MB = 2x +19

2) Make an equation that can satisfy the problem

AM + BM = AB

This is the equation, because if I am to put this on a line,

A M B

-_____________-_____________-

You can see that is you combine the lengths AM and BM you can find the total length of AB.

A M + M B

-_____________- + -_____________-

(M point is actually one point, but I am trying to show that if the line were to be cut in half, then put back together you get you full length, which is AB)

3) Substitute

(5x - 2) + (2x + 19) = AB

4) Now Solve!

5x - 2 + 2x + 19 = AB

(Rearrange to combine like terms)

5x + 2x + 19 - 2 = AB

7x + 17 = AB

(That is your equation to find AB! But they want the specific length)

So...

We solve it!

7x = -17

(By moving the 17 to the other side of the = sign, it becomes negative)

7x = -17

7 7

(Dividing both sides by 7 in order to get x alone)

x = -2.43

(I rounded to the hundredths place)

Now substitute that into x into you original equation)

5(-2.43) - 2 + 2(-2.43) + 19 = AB

-12.15 - 2 - 4.86 + 19 = AB

-14.15 - 4.86 + 19

-19.01 + 19 = -0.01

= -0.01

(I believe this would be the answer, but it doesn't seem to fit right, so please understand, that if this is wrong, I AM SO SORRY ;-;)

(I tried my best on this problem, but I bet it isn't the answer, so if I get this wrong tell me so that I can remove it! :)

User Scott Tesler
by
5.7k points