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3 years ago

A student evaluated −4 + (−9 12) and got an answer of 5 1/2. What might the student have done wrong?

Mathematics

1 answer:

777dan777 [17]3 years ago

3 0

Answer:

The student added +4 instead of -4 so instead of getting -13 1/2 they got 5 1/2 somehow since even if they did that it should be -5 1/2.

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Given: △OKE∼△VDE Prove: EK/EO = ED/EV

harkovskaia [24]

Answer:

The proof is below.

Step-by-step explanation:

Given two triangles similar.

we have to prove that ratio $\frac{EK}{EO}=\frac{VE}{ED}$

As, △OKE∼△VDE

∴ their corresponding sides are in same proportion.

$\frac{OK}{VD}=\frac{EK}{ED}=\frac{OE}{VE}$

⇒ $\frac{EK}{ED}=\frac{EO}{VE}$

⇒ [tex}\frac{EK}{EO}=\frac{VE}{ED}[/tex]

Hence Proved.

6 0

3 years ago

PLEASE HELP ME people I beg you

Paraphin [41]

Equation of circumference is C=2pi times radius
So radius being 32 and pi being 3.14
You would do
2x3.14x32
= 200.96
Hope I helped

3 0

3 years ago

The mean of 100 observation is found to be 40. If at the time of compution two items were wrongly taken as 30 and 27 instead of

Colt1911 [192]

Answer:

40.18

Step-by-step explanation:

According to this question, the mean of 100 observation is found to be 40. This means that the number of values in the set of data is 100. However, at the time of computation two items were wrongly taken as 30 and 27 instead of 3 and 72.

The mean is derived by dividing the sum of values in the data (Σx) by the number of observations (n) i.e.

Mean = Σx/n

For the computation error:

Mean = 40

Let x represent the sun of other 98 values except 30 and 27

n = 100

40 = x + 30 + 27/100

40 = 57 + x/100

Cross multiply

4000 = 57 + x

x = 4000 - 57

x = 3943.

Sum of other 98 values = 3943.

Now, let's find the correct mean with correct values of 3 and 72;

Mean = Σx/n

Mean = 3943 + 3 + 72/100

Mean = 4018/100

Mean = 40.18

7 0

3 years ago

B) Evaluate the algebraic expression 2x2 + 5x +6 if x is equal to (-1).

Korvikt [17]

Step-by-step explanation:

if x is equal to - 1

Then

2x² + 5x + 6

= 2* ( -1)² + 5 * (- 1) + 6

= 2 - 5 + 6

= 8 - 5

= 3

Hope it will help :)❤

5 0

3 years ago

Read 2 more answers

Using the triangle below, answer the following questions.

fomenos

Step-by-step explanation:

Answer(1):

Law of Cosines.

Answer(2):

since side "c" is missing so we will write formula used for side "c"

$c^2=a^2+b^2-2ab\cdot\cos\left(C\right)$

Answer(3):

First lets write both sine and cosine formulas:

Check the attached picture for the list of formulas:

From given picture we see that two angles A and B are missing. Also 1 side "c" is missing.

Sine formula uses two angles while cosine formula uses only one angles.

Hence cosine formula will be best choice to find the missing values.

4 0

3 years ago