Use quadratic formula to solve the following equation​

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since the cosine is the ratio of the adjacent side to the hypotenuse, you can see that cos 60° = ½. answer. according to the property of cofunctions (topic 3), sin 30° is equal to cos 60°. sin 30° = ½.

4y - 6 + y^2 - 9 = y^2 + 4y - 15y^2 term terms- termstotal of 3 terms when simplified