Gio is solving the quadratic equation by completing the square. 5x2 + 15x – 4 = 0. What should Gio do first

We observe that we have a polynomial of the form:
 ax2 + bx + c
 Therefore, to complete the square, we must use the following formula:
 a (x + (b / 2a)) ^ 2 + c - (b ^ 2 / 4a)
 Thus,
 Step 1: 
 We define:
 a = 5
 b = 15
 c = -4
 Step 2: 
 we use the formula:
 5 (x + (15 / (2 * 5))) ^ 2 + (-4) - ((15) ^ 2 / (4 * 5))
 5 (x + (15 / (2 * 5))) ^ 2 - 15.25
 5 (x + 1.5) ^ 2 - 15.25

 5 (x + 3/2) ^ 2 - 61/4

 Answer:
 Gio should do first: 
 a (x + (b / 2a)) ^ 2 + c - (b ^ 2 / 4a)
 a = 5
 b = 15 
 c = -4