Question

The intervals on which x^2+3X-10 is negative x<-5,-52,x>5

Answer 1

please help

Answer 2

if you factor out the equation and set those factors as a table and put the values of the x-intercepts on the bottom you can derive the positive and negative portions of the graph.

Answer 3

can you show me

Answer 4

sure give me a second to draw it.

Answer 5

(x+5)(x-2)

Answer 6

so the graph would be positive from -inf to -5, negative from -5 to 2 and positive from 2 to infiniti

Answer 7

r u confused

Answer 8

VERY

Answer 9

the xintercepts on the bottom you get from setting the factored roots to zero. Which at y=0 you get your x-intercepts. So this is a parabola, because of the leading term X^2, so the negative portion of the parabola is going to be between -5 and 2.

Answer 10

you can also just use the formula to find the vertex of a parabola which is -b/2a.

Answer 11

that will tell you kind of a ball park where the bottom of the parabola is at.

Answer 12

still lost :)

Answer 13

if you see the positive and negative symbols on the bottom of the table I drew, those represent when the graph is negative and when it is positive. In the first column before the negative 5 theres two negatives right. So a negative times a negative equals a positive which is where the positive goes on the bottom. If you take the integer just before -5 and plug it into the factored roots on the left it will give you a positive or negative answer and that's where the positive and negatives come from.