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2. If AB = 4x + 9. BC = 5x + 2, and AC = 56, then find the value for . AB, BC.
A
B

1 Answer

1 vote

Answer:

AB=29; BC=27

Step-by-step explanation:

So they told us AB=4x+9 and that BC=5x+2, and AC=56 , now to help with the question you can draw this information on a number line. Now on a number you can see that basically AC=AB+BC.

So you would write it as such,,

4x+9+5x+2=56

Combine like terms

9x+11=56

Now you have to isolate the x by itself but first get rid of the 11.

9x+11-11=56-11

You would get

9x=45

Here you can divide 9 by both sides to isolate x.

9x/9=45/9

{x=5}

Now to find the value for both substitue x in the equations for both

1. AB=4x+9 where x is 5

4(5)+9 =AB

20+9 =AB

29=AB

You would do the same with BC

2. BC= 5x+2 where x is 5

5(5)+2= BC

25+2= BC

27=BC

If you want to check your answers you can just substitute x for 5 in the first equation we did where AC=AB+BC

User Kgrad
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