Answer:
Formula Of Vertex and Line of symmetry
Step-by-step explanation:
The axis of symmetry always passes through the vertex of the parabola . The x -coordinate of the vertex is the equation of the axis of symmetry of the parabola. For a quadratic function in standard form, y=ax2+bx+c , the axis of symmetry is a vertical line x=−b2a 
Parabolas always have a lowest point (or a highest point, if the parabola is upside-down). This point, where the parabola changes direction, is called the "vertex"
 
        
             
        
        
        
Hello from MrBillDoesMath!
Answer:  x = 1
Discussion
:
Per the author, the equation to solve is  12 = 5x + 7
Isolate the "x" variable by subtracting 7 from both sides of the equation:
12 = 5x + 7
-7 =        -7
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12-7 = 5x + 0
or
5 = 5x
Dividing both sides by 5 gives x - 1
Regards, MrB
 
        
             
        
        
        
Answer:
2y+15
Step-by-step explanation:
y+(15+y)
y+15+y
(y+y)+15
2y+15