2 years ago

Given the quadratic equation: f(x) = x2+4x-21

Mathematics

1 answer:

ryzh [129]2 years ago

6 0

Answer:

x = - 7, x = 3

Step-by-step explanation:

To find the x- intercepts let f(x) = 0 , that is

x² + 4x - 21 = 0

Consider the factors of - 21 which sum to give the coefficient of the x- term (+ 4)

The factors are + 7 and - 3, since

7 × - 3 = - 21 and 7 - 3 = + 4, then

x² + 4x - 21 = 0

(x + 7)(x - 3) = 0 ← in factored form

Equate each factor to zero and solve for x

x + 7 = 0 ⇒ x = - 7

x - 3 = 0 ⇒ x = 3

You might be interested in

If I had seven stones and I threw 8 how many stones do I have left??

igomit [66]

It is impossible as 8 is bigger than 7 and you can’t take it away ur welcome

7 0

3 years ago

Read 2 more answers

LOAD OF QUESTIONS:

Law Incorporation [45]

the end behavior of the function f(x)

the function f(x) must has odd number of roots ( where the graph of a function intersects the x-axis

the width cant be negative so the width of the rectangle would be 8 inches

4 0

2 years ago

Read 2 more answers

True or false? A figure that has opposite sides with equal lengths and equal slopes and diagonals with slopes that are negative

Alex787 [66]

Answer:

False.

Step-by-step explanation:

The diagonals are at right angles ( because of the negative reciprocal slopes)

so it could be a square or a rhombus.

3 0

2 years ago

Can y’all help me out with this

labwork [276]

$(a) P= \frac{A}{e^{rt}} 

(b) e^{rt}= \frac{A}{P} 

ln e^{rt}= ln(\frac{A}{P}), 
rt= ln(\frac{A}{P}), t= \frac{ ln(\frac{A}{P})}{r}, or, t= \frac{ lnA - lnP}{r},
$

5 0

3 years ago

It costs 9,328 points to build each apartment building in the computer game Big city building.What is the cost to build 5 apartm

padilas [110]

Answer:

Mr. Tan buys 4 White Pine trees and 5 Birch trees. What is the ... Then, I added the total cost of the White Pine trees ($148) and the .... It costs 9,328 points to build each apartment building in the computer game Big City Building. What is the ...

Step-by-step explanation:

8 0

2 years ago

Read 2 more answers