3 years ago

If f(x) = x2 – 3x – 40 intersects the x-axis at points A and B, what is the sum of A and B?

Mathematics

1 answer:

Eduardwww [97]3 years ago

4 0

Answer:

Step-by-step explanation:

Intersections on the x axis occur when y = 0. f(x) is another term for y, so set f(x) equal to zero and solve for the two possible x's.

0 = x^2 - 3x - 40

0 = (x-8)(x+5)

By solving for x, you get 8 and -5. 8 and -5 added together will equal 3.

You might be interested in

Factor 5x2 - 7x + 2.

KIM [24]

It might be (5x-2)(x-1)

8 0

3 years ago

A rocket is launched from a tower. the height of the rocket, y in feet, is related to the time after launch, x in seconds, by th

GaryK [48]

Answer: $10.17\ seconds$

Step-by-step explanation:

Given the following Quadratic equation:

$y=-16x^2+153x+98$

The steps to solve it are:

1. Substitute $y=0$ into the equation:

$0=-16x^2+153x+98$

2. Use the Quadratic formula $x=\frac{-b\±\sqrt{b^2-4ac}}{2a}$ .

In this case:

$a=-16\\b=153\\c=98$

Substituting values into the Quadratic equation, you get (Round the values to the nearest hundreth):

$x=\frac{-153\±\sqrt{153^2-4(-16)(98)}}{2(-16)}\\\\x_1=10.17\\x_2=-0.60$

3. The positive value is the time that the rocket will hit the ground.

Therefore, the rocket will hit the ground after $10.17\ seconds$ .

7 0

3 years ago

Are 6/10 and 6/30 multiples of 3/20

ella [17]

Answer:

yes well kinda im pretty sure

Step-by-step explanation:

5 0

3 years ago

Read 2 more answers

If u bring 10 empty bottles to the bottle shop, the bottle shop will change 10 empty bottles to 1 drink. If u bring 100 bottles

Yakvenalex [24]

You will get 10 drinks

8 0

3 years ago

Jill works 10q hours a day. If she earns $6.50 an hour, how much does she earn a day? Give your answer in terms of q.

kolbaska11 [484]

She earns 65 dollars a day replace q with 6.50

6 0

3 years ago

Read 2 more answers