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2 years ago

3(2 + f) = -15A. 3B. 7C. -3D. -7

Mathematics

2 answers:

Scilla [17]2 years ago

5 0

Answer:

D. (-7)

Step-by-step explanation:

3(2 + f) = (-15)

(3 . 2) + (3 . f) = (-15)

6 + 3f = (-15)

3f = (-15) - 6

3f = (-21)

f = (-21)/3

f = (-7)

svp [43]2 years ago

3 0

Step-by-step explanation:

6+3f=-15

subtract 6

3f=-21

then divide

f=-7

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Select two ratios that are equivalent to 7:10

Firdavs [7]

Answer:

7 over 10 and 7,10

Step-by-step explanation:

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3 years ago

Find the value or measure. Assume all lines that appear to be tangent are tangent. X=

aev [14]

According to the secant-tangent theorem, we have the following expression:

$(x+3)^2=10.8(19.2+10.8)$

Now, we solve for <em>x</em>.

$\begin{gathered} x^2+6x+9=10.8(30) \\ x^2+6x+9=324 \\ x^2+6x+9-324=0 \\ x^2+6x-315=0 \end{gathered}$

Then, we use the quadratic formula:

$x_{1,2}=\frac{-b\pm\sqrt[]{b^2-4ac}}{2a}$

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$\begin{gathered} x_{1,2}=\frac{-6\pm\sqrt[]{6^2-4\cdot1\cdot(-315)}}{2\cdot1} \\ x_{1,2}=\frac{-6\pm\sqrt[]{36+1260}}{2}=\frac{-6\pm\sqrt[]{1296}}{2} \\ x_{1,2}=\frac{-6\pm36}{2} \\ x_1=\frac{-6+36}{2}=\frac{30}{2}=15 \\ x_2=\frac{-6-36}{2}=\frac{-42}{2}=-21 \end{gathered}$ <h2>Hence, the answer is 15 because lengths can't be negative.</h2>

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1 year ago

A trucking firm has a large inventory of spare parts that have been in storage for a long time. It knowsthat some proportion of

Debora [2.8K]

Answer:

$0.1546\leq \widehat{p}\leq 0.3513$

Step-by-step explanation:

The firm tests 75 parts, and finds that 0.25 of them are notusable

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$\widehat{p}=\frac{x}{n}$

$\widehat{p}=\frac{19}{75}$

$\widehat{p}=0.253$

Confidence level = 95%

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Formula of confidence interval of one sample proportion:

$=\widehat{p}-Z_\alpha \sqrt{\frac{\widehat{p}(1-\widehat{p}}{n}}\leq \widehat{p}\leq \widehat{p}+Z_\alpha \sqrt{\frac{\widehat{p}(1-\widehat{p}}{n}}$

$=0.253-(1.96)\sqrt{\frac{0.253(1-0.253)}{75}}\leq \widehat{p}\leq0.253+(1.96)\sqrt{\frac{0.253(1-0.253}{75}}$

Confidence interval $=0.1546\leq \widehat{p}\leq 0.3513$

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3 years ago

Lee Middle School orders 15 textbooks for every 12 students. The table shows how many textbooks the school orders for certain nu

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Answer: 90 textbooks

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3 years ago

AC has endpoints<br> A(3,7) and C(6,11).<br> Find AB if B is the<br> midpoint of AC.

faltersainse [42]

Answer:

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Step-by-step explanation:

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since B is the mid point : d/2=5/2=2.5

<h2>Another way :</h2>

B(x1+x2/2 , y1+y2/2) , x1=3 , x2=6, y1=7, y2=11

B(9/2,18/2)

B(9/2,9)

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d=√(x2-x1)²+(y2-y1)²

d=√(3-9/2)²+(7-9)²

d=√(-3/2)²+(-2)²

d=√1.5²+4

d=√6.25

d=2.5

8 0

3 years ago

3(2 + f) = -15A. 3B. 7C. -3D. -7​

3(2 + f) = -15A. 3B. 7C. -3D. -7