Question

how can you show the quadratic function y = 2x2 + 8x + 7? in a graph? how would it look drawn in a graph

Answer 1

@e.cociuba

Answer 2

The x² coefficient is positive and so the graph would be concave up ("U-shaped")

Answer 3

go to http://www.meta-calculator.com/online/ it will graph the function for youand s

Answer 4

to graph any parabola of the type \(\large ax^2+bx+c\)
first off, you can start by noticing that the "a" coefficient is positive, that means the parabola is going upwards

then use the vertex of it, you can get the vertex at \(\bf \left(-\cfrac{b}{2a}\quad ,\quad c-\cfrac{b^2}{4a}\right)\)

then just pick 2 points, on the left of the vertex, and one to the right, and draw it

Answer 5

and if the a is going up then it's minimum right?

Answer 6

Yes the equation will have a minimum but no maximum.

Answer 7

ok so now what do i need to do?

Answer 8

and thank you @DSS for the link i will certainly check it out

Answer 9

There are a few other properties:
2x2 + 8x + 7
If b² - 4*a*c is positive, the graph crosses the x axis and the roots are real.
8² - 4*2*7
Since it is positive, then graph crosses x axis and both roots are real.
Look at all you learned and you didn't have to graph anything.

Answer 10

ok thank you so much for the help i got the answer you are all the best and i wish i'm as smart as you guys <3

Answer 11

Thanks :-)