F(x) = x² + x - 20 = x² + 5x - 4x - 20 = x(x + 5) - 4(x + 5) = (x + 5)(x - 4)

f(x) = 0 ⇔ (x + 5)(x - 4) = 0 ⇔ x + 5 = 0 or x - 4 = 0 ⇒ x = -5 or x = 4

Answer: C. x = -5 and x = 4.

3 0

3 years ago

The length of a rectangle is twice the with. If the perimeter of the rectangle is 60 units, find the area of the garden

Darya [45]

w - width

2w - length

60 - perimeter

w + w + 2w + 2w = 6w - perimeter

The equation:

6w = 60 <em>divide both sides by 6</em>

w = 10 → 2w = 2 · 10 = 20

The area: A = width × length

A = (10)(20) = 200

<h3>Answer: The area of the garden is equal 200 square units.</h3>

4 0

3 years ago

Please help with this algebra :)

Dahasolnce [82]

I am gonna go for D is the answer.

8 0

4 years ago

Mrs Smith is completing a mathematics problem. She knows when 6 is added to four times a number, the result is 50. What would be

Lesechka [4]

EXPLANATION:

-To formulate an equation, you must first know what data the exercise gives us to locate them correctly.

data:

-6 that must be added to a number.

-four times a number that is equal to 4x

-a result that is equal to 50

Now with these data we formulate the equation:

$\begin{gathered} \text{Equation:} \\ 6+4x=50;\text{ } \end{gathered}$

if we solve the equation we have:

$\begin{gathered} 6\text{ }+4x=50 \\ 4x=50-6 \\ 4x=44 \\ x=\frac{44}{4} \\ x=-\frac{22}{2} \\ x=\text{ }-11 \end{gathered}$

6 0

1 year ago