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3 years ago

ABCD is a trapezoid. segment AB = 1 cm and segment CD = 5 cm, and the area = 7.5 cm2. What is the altitude of the trapezoid?

Mathematics

2 answers:

kati45 [8]3 years ago

7 0

Answer: 2.5 cm

Step-by-step explanation:

We know that area of trapezoid A = $\frac{1}{2}h(a+b)$ , where a and b are the opposite sides of trapezoid and h is the altitude of the trapezoid.

Given: AB = 1 cm and CD = 5 cm, and the area = 7.5 square cm.

By the name of trapezoid we can see that AB and CD are opposite sides of trapezoid, then

Area of trapezoid= $\frac{1}{2}h(AB+CD)=7.5\ cm^2$

$\Rightarroe\frac{1}{2}h(1+5)=7.5\\\Rightarrow\ h(6)=2\times7.5\\\Rightarrow\ h=\frac{2\times7.5}{6}\\\Rightarrow\ h=2.5$

Hence, the altitude of the trapezoid = 2.5 cm

JulijaS [17]3 years ago

6 0

Area of a trapezoid = 1/(a + b)h; where a and b are the two parallel sides and h is the height (altitude).
7.5 = 1/2(1 + 5)h = 1/2(6)h = 3h
h = 7.5/3 = 2.5 cm.

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Step-by-step explanation:

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TEA [102]

Answer:

(a) Null Hypothesis, $H_0$ : $\mu$ = $1,150

Alternate Hypothesis, $H_A$ : $\mu$ $\neq$ $1,150

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(c) We conclude that the mean of all account balances is significantly different from $1,150.

Step-by-step explanation:

We are given that a sample of 81 account balances of a credit company showed an average balance of $1,200 with a standard deviation of $126.

We have test the hypothesis to determine whether the mean of all account balances is significantly different from $1,150.

Let $\mu$ = mean of all account balances

(a)So, Null Hypothesis, $H_0$ : $\mu$ = $1,150 {means that the mean of all account balances is equal to $1,150}

Alternate Hypothesis, $H_A$ : $\mu$ $\neq$ $1,150 {means that the mean of all account balances is significantly different from $1,150}

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where, $\bar X$ = sample average balance = $1,200

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