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3 years ago

10 POINTS!! HELP ASAP!! What is the length of AC?

Mathematics

2 answers:

il63 [147K]3 years ago

8 0

Answer:

D. 144

Step-by-step explanation:

Triangle BAC is similar to triangle DEC, so you can set up a ratio:

$\frac{84}{156-x} = \frac{7}{x}$

Then cross multiply

84x = 7 (156 - x)

84x = 1092 - 7x

Add 7x to both sides.

91x = 1092

Divide both sides by 91.

x = 12

AC = 156 - x

AC = 156 - 12

AC = 144

My name is Ann [436]3 years ago

4 0

Answer:

Step-by-step explanation:

Δ CED and Δ CAB are similar thus the ratios of corresponding sides are equal, that is

$\frac{CE}{CA}$ = $\frac{ED}{AB}$ , substitute values

$\frac{x}{156-x}$ = $\frac{7}{84}$ = $\frac{1}{12}$ ( cross- multiply )

12x = 156 - x ( add x to both sides )

13x = 156 ( divide both sides by 13 )

x = 12

Thus

AC = 156 - x = 156 - 12 = 144 → D

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Comment
(my edit) it is not that 2/15 is wrong (although it is not entirely right).
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The two of us who have responded have really responded to what are the chances of drawing 2 white chips. The question really does not restrict us in a way that prevents us from saying that. I'll stick with
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The semi right answer is B <<<<----

If my reasoning bothers anybody, I'll reedit again. I'm only leaving it because sometimes a mistake is more instructive than a given answer.

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