3 years ago

Work out the size of angle a AB = 11cm AC = 9cm

Mathematics

1 answer:

Papessa [141]3 years ago

8 0

Step-by-step explanation:

simply use trig ( cos)

so cosx°= 9/11

now do cos^-1 x°(9/11) in a calculator to find the value of the angle

that will result in 35.09°

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gogolik [260]

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3 years ago

Multiply.<br> (d+7)(d-7)<br> Simplify your answer.

romanna [79]

Answer:

$\huge\boxed{(d+7)(d-7)=d^2-49}$

Step-by-step explanation:

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