I need help with these questions (see image). Please show workings.
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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 = = 12

Then

length of chord = 2x = 2 × 12 = 24 cm

it is a. 4.2 because 7.6-3.4 gets the remaining length of 4.2. i might be wrong but i am pretty sure this is the answer.