Answer:
See explanation
Step-by-step explanation:
1. Factor the function 

2. The zeros (or the solutions of the equation f(x)=0) are x=3 and x=5. So? points (3,0) and (5,0) are the points on the graph that are the solutions of the equation.
3. Find the vertex:

Thus, the coordinates of the vertex are (4,2) and the axis of symmetry is the vertical line that passes trough the vertex: x=4.
Answer:
30 pounds
Step-by-step explanation:
Amount of tin in first alloy + amount of tin in second alloy = amount of tin in mixture
0.15 (20) + 0.10 x = 0.12 (20 + x)
3 + 0.10 x = 2.4 + 0.12 x
0.6 = 0.02 x
x = 30
First you expand the brackets, so
36 + 6y = 9 - 3y
Then you get all the y's on one side
+ 3y
36 + 9y = 9
- 36
9y = 9
Then you divide by 9 to get y by itself
y = 1