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3 years ago

Write a quadratic equation in the form ax^2+bx+c=0 with roots of -4 and 5

Mathematics

1 answer:

Stolb23 [73]3 years ago

7 0

Step-by-step explanation:

- 4 & 5 are roots

Therefore, (x + 4) & (x - 5) are factors.

Required quadratic equation is given as:

$(x + 4) (x - 5) \\ = x(x - 5) + 4(x - 5) \\ = {x }^{2} - 5x + 4x - 20 \\ = {x}^{2} - x - 20 \\$

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Graphing this equation -x+4y=8

Keith_Richards [23]

The linear form of that equation is y=1/4x+2. Your y-intercept should be 2 and the slope is 1/4.

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2 years ago

A ferry departs from a port along the Sands River at 10:00 am. The ferry travels at a speed of 15 mph in still water and returns

jek_recluse [69]

Answer:

Speed of river's current = 5 mph

Step-by-step explanation:

Let 'd' be the distance covered

Let x be the speed of the rivers current

Speed upstream = 15-x

speed downstream = 15+x

Time = distance / speed

time upstream = $\frac{d}{15-x}$

time downstream = $\frac{d}{15+x}$

the ferry trip upstream takes twice as long as its return trip downstream

$\frac{d}{15-x}$ = $\frac{2d}{15+x}$

divide both sides by d

$\frac{1}{15-x}$ = $\frac{2}{15+x}$

cross multiply

$15+x= 2(15-x)$

$15+x= 30-2x$

Add 2x on both sideds

$15+3x= 30$

subtract 15 from both sides and divide by 3

$3x=15$

x=5

Speed of river's current = 5 mph

8 0

3 years ago

21. Melanie is making homemade stickers, She uses

Sergio039 [100]

1: 5 2: 9 or 10

For question 1 we can round 115 to 100, 5x100 is 500 which is closer to 545 than 7x100 = 700.

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3 years ago

Witch of the following best describes the slope of the line below

ankoles [38]

Answer- undefined slope

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3 years ago

Read 2 more answers

Is this the correct answer?

andreev551 [17]

Answer:

y = 3x + 5

General Formulas and Concepts:

Algebra I

Slope-Intercept Form: y = mx + b

m - slope

b - y-intercept

Step-by-step explanation:

Step 1: Define variables

Slope m = 3

y-intercept b = 5

Step 2: Write linear equation

y = 3x + 5

6 0

3 years ago