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The equation of a parabola is given. y=18x2+4x+20 what are the coordinates of the focus of the parabola?

Which is a logical conclusion based on the given information? a. figure abcd is a rhombus by the definition of a rhombus. b. segment ac is congruent to segment dc by cpctc. c. angle acb is congruent to angle adc by the angle-side-angle theorem. d. triangle acd is congruent to triangle cab by the hypotenuse-leg theorem.

The sales tax for an item was $8.40 and it cost $420 before tax. find the sales tax rate. write your answer as a percentage.