Answer:

Step-by-step explanation:
The equation of a quadratic function in vertex form is given by:

Where (h,k) is the vertex.
It was given in the question that the vertex of the parabola is (-1,4).
When we substitute the vertex into the formula we get:

The parabola also passes through (4,19) hence it must satisfy its equation.



We divide both sides by 25 to get:

Hence the quadratic function is:

Yes they do, Hope this helps :p
Answer: first one 5.55
Step-by-step explanation:
-4x+8=42
-4x+8-8=42-8
-4x=34
-4x=34
-4x/-4=34/-4
x= - 17/3
Answer:
b. -1
Step-by-step explanation:
9=4a+13
-13 -13
--------------
-4=4a
4a/-4
a=-1