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2 years ago

The roots of a quadratic equation are 4 and -5. Which quadratic equation has these roots?

Mathematics

1 answer:

Y_Kistochka [10]2 years ago

8 0

Answer:

(x-4)(x+5) or x^2+x-20

Step-by-step explanation:

If a root of the function is 4, (meaning that when y=0, x=4) it can be rewritten as x-4.

The same goes for if a root is -5. it will simplify to x+5.

These are called factors of a quadratic equation.

Put together, they look like (x-4)(x+5). Using the FOIL method, that can be simplified to x^2+x-20

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Convert from Decimal Notation to Scientific Notation

umka21 [38]

Answer:

Hence, 0.026 can be expressed as $2.6 \times 10^{-2}$ .

Step-by-step explanation:

- Given 0.026

- Use given, move the decimal point so that first factor is greater than or equal to 1 but less than 10 .

- Then count n and write in scientific notation.

Step 1 of 1

Consider 0.026

$\Rightarrow 2.6$

Decimal has moved 2 places to right.

The power will be negative as original no. is less than 1 .

$\begin{aligned}&2.6 \times 10^{-2} \\&0.026=2.6 \times 10^{-2} .\end{aligned}$

6 0

2 years ago

What is the solution I don't get it plz help

Nataliya [291]

Ooooohhh i'm am so sorry. The best thing u can do is ask your teacher & leave it blank!!! If I knew, I would love to help if i knew though!!!!

6 0

3 years ago

Read 2 more answers

areas of four triangles are 40 cm^2, 90 cm^2, 202.5 cm^2 and 455.6 cm^2 are continue in sequence. the enlargement factor is 1.5,

maw [93]

Answer:

9th Triangle

Step-by-step explanation:

Given the area of four triangles: $40 cm^2, 90 cm^2, 202.5 cm^2 \:and\: 455.6 cm^2$

If the Scale factor is 1.5.

This is a geometric sequence and the common ratio is 1.5 X 1.5.

Therefore, the area of any n triangle can be determined using the function:

$A(n)=40\cdot1.5^{2(n-1)}$

We want to determine which triangle has an area greater than $15000cm^2$ .

When A(n)=15000

$40\cdot1.5^{2(n-1)}>15000\\1.5^{2(n-1)}>\frac{15000}{40} \\1.5^{2(n-1)}>375\\\text{Change to Logarithm form}\\2(n-1)>Log_{1.5}375\\\text{Applying logarithm change of base to base 10 law}\\2(n-1)>\frac{Log 375}{Log 1.5} \\2n-2>14.62\\2n>14.62+2=16.62\\n>8.31$

Therefore, the 9th triangle has an area greater than $15000cm^2$ .

5 0

3 years ago

Calculeaza aria unu paralelogram cu latura 3 radical 2 cm si inaltimea 2cm

zloy xaker [14]

Answer:

Aria unui paralelogram $=6\sqrt{2}$

Step-by-step explanation:

Folosind formula:

Aria unui paralelogram = (baza x înălțimea)

= (3√2 x 2)

$=6\sqrt{2}$

Aria unui paralelogram $=6\sqrt{2}$

6 0

3 years ago

If a storm window has an area of 640 square inches, what is the equation to find the dimensions when the window is 20 inches hig

Lyrx [107]

Area = width * height
since the window is 20 inches higher than the width:
width +20 = height

640 = width * width+20
640 = width^2 +20*width
width^2 +20*width - 640 = 0
width = 17.203
**********************************************************
Double Check
if width = 17.203 then height = 37.203
area = 17.203 * 37.203 = 640 square inches Correct!!

8 0

3 years ago