Can someone one help me pls

I just need 8, 9 and 10

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Terri makes a quilt using three sizes of fabric squares the side lenght of each fabric square is the square root of the area

Given: m∠ adb = m∠cdb ad ≅ dc prove: m∠ bac = m∠bca lol

Express the following as a function of a single angle. cos(60) cos(-20) - sin(60) sin(-20)