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2 years ago

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the area of a parallelogram measures 171 cm the base of the parallelogram is 18 cm in length which of the following best represe

nts the height of the parallelogram A. 11cm B. 9.5 C. 13.5 D. 8cm give step by step explanation

1 answer:

goblinko [34]2 years ago

3 0

Answer:

A=bxh

171 cm=18cmxh

h=171/18

= 9.5 cm

which is B no.

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If a,b,c and d are positive real numbers such that logab=8/9, logbc=-3/4, logcd=2, find the value of logd(abc)

Eva8 [605]

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Then using the change of base formula, we can derive the relationship

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###

Another way to do this:

$\log_ab=\dfrac89\implies a^{8/9}=b\implies a=b^{9/8}$

$\log_bc=-\dfrac34\implies b^{-3/4}=c\implies b=c^{-4/3}$

$\log_cd=2\implies c^2=d\implies\log_dc^2=1\implies\log_dc=\dfrac12$

Then

$abc=(c^{-4/3})^{9/8}c^{-4/3}c=c^{-11/6}$

So we have

$\log_dabc=\log_dc^{-11/6}=-\dfrac{11}6\log_dc=-\dfrac{11}6\cdot\dfrac12=-\dfrac{11}{12}$

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