Tell whether the graph opens upwards or downward and whether the parabola has a maximum or minimum y=-x2-7x+18
1 answer:
Answer:
Downwards, maximum
Step-by-step explanation:
In a <em>quadratic function </em>- one of the form where a, b, and c are all constant - the direction of the parabola is determined by <em>a. </em>If a is <em>positive</em>, the parabola opens upward - it has no maximum, since it shoots up infinitely in the positive y direction, but it does have a minimum; if you dropped a marble inside the parabola, it's the point where that marble would eventually rest. If a is <em>negative</em>, our parabola opens in the <em>negative</em> y direction, and the graph has a maximum. To use the marble analogy, the maximum is the one point where the marble won't roll off the sides of the graph.
Our function has a = -1, so it opens <em>downward</em> and has a <em>maximum point</em>.
You might be interested in
First of all, let's explain the term relation. Many everyday phenomena involve two quantities that can be related to each other by some rule of correspondence. In mathematics the term for such a rule of correspondence is called relation. Relations are often represented by mathematical equations and formulas.
Suppose you have a set A and a set B, so if a relation assigns to each element
in the set A exactly one element 
in the set B, then the function 
is in fact that relation.
Suppose you have a set A and a set B, so if a relation assigns to each element