Mathematics, 17.03.2020 17:20 Frenchfries13

Solve x2+4x+6=0 by graphing

Answers: 2

Show answers

Answers

Answer from: blakestuhan

x = -2±√2 i or no real roots. See the explanation below.

Step-by-step explanation:

If you draw the graph, you will notice that there are no common points or you can say that there are no x-intercepts.

This means that the equation doesn't have any real roots.

If there are 2 common points (2 x-intercepts) then there are 2 real roots (answers.)

If there is only one common point (vertex is on x-axis) then there is only 1 real root.

If there aren't any common points (no x-intercepts) then there are no real roots.

So first, I'm gonna convert the equation into function and convert the standard form to vertex form.

$x^2+4x+6=0\\y=x^2+4x+6\\y=(x^2+4x+4)-4+6\\y=(x+2)^2+2$

We notice that the vertex is at (-2,2), the graph doesn't have x-intercepts (Graph below)

So the answer is clearly complex.

If you solve this by solving the equation then it'll be.

$x^2+4x+6=0\\x= \frac{-b+-\sqrt{b^2-4ac}}{2a} \\x=\frac{-4+-\sqrt{16-24} }{2}\\x=\frac{-4+-\sqrt{-8} }{2}\\\\x=\frac{-4+-2\sqrt{2}i }{2}\\\\x={-2+-1\sqrt{2}i }\\\\$

The answer is complex.

However, you can find the value of x easily by graphing. For example.

x^2+6x+5=0

Factor then you get

$(x+5)(x+1)=0\\x=-5,-1$

Or you can convert it to vertex form then graph.

y=x^2+6x+5

$y=(x^2+6x+9)-9+5\\y=(x+3)^2-4$

The vertex is at (-3,-4) then graph parabola (x-intercepts determine the roots of quadratic equation. For the graph, parabola intercepts x at (-5,0) and (-1,0) that means both -5 and -1 both are the value of x.

Note:

From the standard form, y=ax^2+bx+c The graph is called Parabola, and it's Quadratic Function.

a is how the graph is, for example. If a>0, the graph is supine parabola and if a<0 then the graph is inverted parabola.

|a| is determined if the graph is wide or narrow, the more the value of a is, the more narrow it will be. The less the value of a is, the more wide it will be.

b is what determined the change of graph (likely vertex). Without b, then it'd be ax^2+k which only move y-axis and not x-axis.

c is what determined the y-intercept and y-axis. If there is no b or the value of b is 0 then the vertex is at (0,c). If there is the value of b then c is only determined the y-intercept.

Answer from: Quest

Peanuts r great aren’t they it just has a good taste

Answer from: Quest

walter needs to make at least 5 more cookies but no more than 40. 5 ≥ x ≥ 40;

step-by-step explanation:

walter has to make a minimum of 20 cookies. he already has 15 cookies made, so he must make 5 more to meet the minimum.

the maximum amount of cookies he can make is 55. he already has 15, so he has to make no more than 40 more cookies to meet the maximum.

Another question on Mathematics

Mathematics, 21.06.2019 13:00

What is the y-coordinate of the solution of the system of equations? [tex]y = 2x + 14 \\ - 4x - y = 4[/tex]y=

Answers: 1

Answer

Mathematics, 21.06.2019 19:30

Jada has a meal in a restaurant she adds up the prices listed on the menu for everything they ordered and gets a subtotal of $42.00. when the check comes, it says they also need to pay $3.99 in sales tax. what percentage of the subtotal is the sales tax

Answers: 2

Answer

Mathematics, 21.06.2019 19:30

The measure of an angle is 117°. what is the measure of a supplementary angle?

Answers: 2

Answer

Mathematics, 21.06.2019 20:30

The graph of y x3 is translated so that the point (1. 1) is moved to (1, 4). what is the equation of the new graph?

Answers: 1

Answer

You know the right answer?

Solve x2+4x+6=0 by graphing...