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3 years ago

What is the sum of the first 4 terms of the arithmetic

1 answer:

8 0

$a_6=8;\ a_{10}=13\\\\a_{10}-a_6=4r\\\\4r=13-8\\4r=5\ \ \ \ /:4\\r=1.25\\\\a_1=a_6-5r\\a_1=8-5\cdot1.25=8-6.25=1.75\\\\S_4=\frac{2a_1+(4-1)r}{2}\cdot4=(2a_1+3r)\cdot2=4a_1+6r\\\\S_4=4\cdot1.75+6\cdot1.25=7+7.5=14.5$

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Which congruence theorems can be used to prove ΔABR ≅ ΔACR? Select three options.

sergejj [24]

Answer:

1. HL

2. SAS

3. SSS

Step-by-step explanation:

Triangles ABR and ACR share side AR (hypotenuse of two right triiangles).

Angles ABR and ACR are right angles.

Sides AB and AC are congruent.

Sides BR and CR are congruent.

1. You can use HL theorem, because two triangles have congruent pair of legs and congruent hypotenuses.

2. You can use SAS theorem, because two triangles have two pairs of congruent legs and a pair of included right angles between these legs.

3. You can use SSS theorem, because two triangles have two pairs of congruent legs and congruent hypotenuses.

4 0

3 years ago

Read 2 more answers

Which number is a counting number? Can you do both of them plz

DochEvi [55]

Question 3 is: D. All integers are rational numbers.
Question 4 is: C. the counting number is 4. Hope this helped :)

4 0

3 years ago

there are 300 student and teachers at a sports event.Grade k to 2 is students: 137 Grade 3 to 5 students: 145 Teachers: ? what i

AVprozaik [17]

Answer:

Percentage of teachers = 6%

Step-by-step explanation:

Given;

Number of grade k-2 students = 137

Number of grade 3-5 students = 145

Total = 300

Number of teachers = 300 - (137+145) = 18

Percentage of teachers = (number of teachers÷total)× 100%

%T = (18/300) × 100

%T = 6%

8 0

3 years ago

A brand new filled can of chicken broth is 10 cm tall and has a radius of 10 cm. Mishka uses some of the broth to cook and now t

Maurinko [17]

we have chicken broth in cylindrical can.

we have given the height radius of cylindrical can.

h=10cm r=10 cm .

and she have 6cm broth height in the tin that means she had used 4 cm of height of broth .

now we need to find volume of two cylinder with h=10 cm and 6cm

and we need to find the difference between the volumes .

volume1= $\pi *r*h_{1} =\pi *(10)^2*10=3.14*1000=3140 cm^3$

volume 2= $\pi *(10)^2*6=1884cm^3$

volume used =volume 1-volume2=3140-1884=1256cm^3 is used

8 0

3 years ago

Read 2 more answers

2. The hundredths model is shaded to represent a division

solniwko [45]

Answer:

Option D

Step-by-step explanation:

If the whole grid is considered to be 1,

Each small grid will value = $\frac{1}{100}=0.01$

There are 72 shaded grids which represent the hundreds = 0.72

When these grids have been divided into 9 equal rows, number of grids in each row = 8

And the value of 8 grids in each row = 0.01 × 8 = 0.08

So the equation is,

0.72 ÷ 9 = 0.08

Therefore, equation represented by the model will be Option (D).

4 0

3 years ago