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2 years ago

Circle with O as the centre. RS is a tangent to the circle. Calculate:

Mathematics

1 answer:

SCORPION-xisa [38]2 years ago

8 0

Answer:

It is a right triangle.

So, using Pythagorean theorem: OS² = OR² - RS²

OR = r (radius) + 8

OS = r

RS = 16

=> r² = (r+8)² - 16²

r² = r² + 16r + 64 - 256

r² = r² + 16r - 192

16r = 192

r = 192 / 16 = 12cm²

a) 12 cm²

b) 12 + 8 = 20 cm²

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5x+y=-10 4x-7y=-8 Substition Method (Show it step by step please!)

Fynjy0 [20]

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3 years ago

Read 2 more answers

There are 135 people in a sport centre. 73 people use the gym. 59 people use the swimming pool. 31 people use the track. 19 peop

Sonbull [250]

Answer:

24 people

Step-by-step explanation:

((The numbers are up there, so I am not going to define each variable.))

For starters, there is no overlap between the double facilities groups, except the triple facility users, so:

19 + 9 + 16 - 4 = 40 people

Since there is overlap between single and double groups, you will need to subtract, so:

Gym: 73 - 19 - 16 = 38

Pool: 59 - 19 - 9 = 31

Track: 31 - 9 - 16 = 6

Total for 1 facility: 38 + 31 + 6 - 4 = 71 people

((Minus 4 because the 4 triple facility users overlap the double facility users (problem is in layers: layer 1 minus layer 2, then minus layer 3).))

Next, add the totals:

71 + 40 = 111 people (using facilities)

135 - 111 = 24 people (who didn't use any)

(((I'm not 100% sure on this answer, so if someone could check my work, that would be much appreciated.)))

4 0

3 years ago

The number of seats in a row has been increased at a rectangular-shape movie theater after renovation so that it is now five mor

Damm [24]

Let the number of rows be = r

Let the number of seats per row be = s

we know that the number of seats is 126.

So, $s\times r=126$ ..... (1)

As given, there are five more seats per row than the number of rows, so we can say that:

$s=r+5$

Putting this in equation (1)

$(r+5)*r=126$

$r^{2}+5r=126$

$r^{2}+5r-126=0$

$r^{2}+14r-9r-126=0$

$(r+14)(r-9)=0$

r=-14 and r=9 (neglecting the negative value) we get r=9

And s=r+5

so, s =9+5=14

Hence, there are 5 rows and 14 seats per row.

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3 years ago

I will mark you brainlist and give 5 stars! Please help!

mrs_skeptik [129]

Answer:

9A-F

9B-EI

9C-FG

Step-by-step explanation:

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3 years ago

Read 2 more answers

…………………………………………………………………………………………………………………….…………………

ale4655 [162]

We can split this up into 3 rectangles. 2 vertical ones (8 x 3) and one horizontal one in the middle (5 x (8 - 5)

8 x 3 = 24
24 x 2 = 48

5 x (8-5) = 5 x 3 = 15

now add 48 + 15 = 63 cm^2

6 0

3 years ago