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Which graph represents the given equation?

y = :2 + 41 - 2
O. A.
N
X
2
N
-21
B.
ܢܬ
#
2
-21
N
+21
C.

Which graph represents the given equation? y = :2 + 41 - 2 O. A. N X 2 N -21 B. ܢܬ # 2 -21 N-example-1
User Reynolds
by
4.0k points

1 Answer

1 vote

9514 1404 393

Answer:

A

Explanation:

The axis of symmetry of quadratic ax²+bx+c is x=-b/(2a). For the given equation, the axis of symmetry is ...

x = -4/(2(3/2)) = -4/3

The only graph with its vertex at x=-4/3 is graph A.

_____

Additional comment

You can also make the correct choice by evaluating the equation at a couple of different values of x. Convenient ones are x= -1, or 0, or +1. The value at x=0 is the y-intercept, (0, -2), which seems to be a point on all of the graphs. The value at x=1 is 3/2+4-2 = 3.5, which looks like it is only seen on graph A.

User Jonathan H
by
3.8k points