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3 years ago

I need help with these questions (see image). Please show workings.

Mathematics

2 answers:

Anton [14]3 years ago

5 0

Answer:

24 cm

Step-by-step explanation:

The chord, if the ends connected with the center, form an isosceles triangle with two sides being a radius of the circle.

We have:

Length of chord = x
Height of triangle = h = 5 cm
Radius = r = 26/2 = 13 cm

From the triangle we get:

(x/2)² + h² = r²
x²/4 + 5² = 13²
x²/4 = 144
x/2 = 12
x = 24

The length of the chord is 24 cm

denpristay [2]3 years ago

4 0

Answer:

24 cm

Step-by-step explanation:

The altitude from the centre to the chord is 5 cm and bisects the chord.

The radius of the circle is 26 cm ÷ 2 = 13 cm

There is a right triangle formed with legs 5 and x ( x is half the chord )

The hypotenuse is the radius, then using Pythagoras' identity

x² + 5² = 13²

x² + 25 = 169 ( subtract 25 from both sides )

x² = 144 ( take the square root of both sides )

x = $\sqrt{144}$ = 12

Then

length of chord = 2x = 2 × 12 = 24 cm

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Normal probability distribution

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