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Which equation could solved using the graph above

Which equation could solved using the graph above-example-1
Which equation could solved using the graph above-example-1
Which equation could solved using the graph above-example-2
User Trancot
by
6.1k points

2 Answers

4 votes

Answer:

x2 + 3x + 2 = 0

Explanation:


x^(2) + 3x + 2 = 0


(x + 2) (x + 1) = 0


x + 2 = 0 | x +1 = 0


x = -2 | x = -1

The points for the x-coordinates are -2 and -1


(-2)^(2) + 3(-2) +2 | (-1)^(2) + 3(-1) + 2


4 - 3 + 2 | 1 - 3 + 2

0 = 0

These points work.

Which equation could solved using the graph above-example-1
User Perazzo
by
7.2k points
2 votes
Notice all the important features of the graph,

1) The graph is a parabola;
2) Roots are -2, -1
3) A point is (-3, 2)

Put all this information into an equation;

y=a(x-r)(x-s)
y=a(x+1)(x+2) <-- signs revered due to the negative sign
2=a(-3+1)(-3+2) <-- put in the values of x and y to find a
2=a(-2)(-1)
2=a(2)
2/2=a
1=a

y=(x+2)(x+1) <-- find in standard form by expanding
y= x²+x+2x+2
y=x²+3x+2

Therefore, the correct option is the second one;

Hope I helped :)
User Jeda
by
6.9k points
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