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2 years ago

A train is traveling at 60 mph. If the rate of speed increases 4 mph each hour,

Mathematics

1 answer:

Alenkasestr [34]2 years ago

6 0

Answer:

B) 5 hours

Step-by-step explanation:

First, find the amount of mph between 60 and 80:

80 - 60

= 20 mph

Since the speed increases 4 mph per hour, we can find how long it will take to get to 80 mph by dividing 20 by 4:

20/4

= 5

So, the correct answer is B, 5 hours

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Z+11≤17<br> What is the answer?

Art [367]

Answer:

Z is less than or equal to 6

Step-by-step explanation:

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3 years ago

What is the value of y in the equation 2 + y = −3? (1 point)

Ilya [14]

Answer:

- 5

Step-by-step explanation:

2 + y = −3

Subtract 2 from both sides

2 + y - 2 = −3 - 2

Simplifying

y = -5

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3 years ago

Need help to do this step by step please <br> 3x2 - 2x=-1

sdas [7]

Answer:

Solving the expression $3x^2-2x=-1$ we get: $\mathbf{x=\frac{1+\sqrt{2}i }{3}\:or\:x=\frac{1-\sqrt{2}i }{3}}$

Step-by-step explanation:

We need to solve the expression: $3x^2-2x=-1$

This is a quadratic expression and it can be solved using quadratic formula

Solving:

$3x^2-2x=-1\\$

we can write it as:

$3x^2-2x+1=0$

The quadratic formula is: $x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}$

where a = 3, b = -2 and c= 1

Putting values and solving:

$x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}\\x=\frac{-(-2)\pm\sqrt{(-2)^2-4(3)(1)}}{2(3)}\\x=\frac{2\pm\sqrt{4-12}}{2(3)}\\x=\frac{2\pm\sqrt{-8}}{6}\\We\:know\:that\:\sqrt{-1}=i\\x=\frac{2\pm\sqrt{8}\sqrt{-1} }{6} \\We\:know\:\sqrt{8}=\sqrt{2\times 2 \times 2}=\sqrt{2^2 \times 2}=2\sqrt{2} \\x=\frac{2\pm2\sqrt{2}i }{6}\\Now,\\x=\frac{2+2\sqrt{2}i }{6}\:or\:x=\frac{2-2\sqrt{2}i }{6}\\x=\frac{2(1+\sqrt{2}i) }{6}\:or\:x=\frac{2(1-\sqrt{2}i) }{6}\\x=\frac{1+\sqrt{2}i }{3}\:or\:x=\frac{1-\sqrt{2}i }{3}$

So, solving the expression $3x^2-2x=-1$ we get: $\mathbf{x=\frac{1+\sqrt{2}i }{3}\:or\:x=\frac{1-\sqrt{2}i }{3}}$

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3 years ago

A large school district is reevaluating its teachers' salaries. They have decided to use regression analysis to predict mean tea

inna [77]

Answer:

a) Y = 35,422.12

b) Y = 29,367.67

c) 1,210.89

Step-by-step explanation:

The salary of teachers is forecasted by the following equation,

Y = 23,313.22 + 1,210.89X

Where Y is the forecasted salary and X is the years of experience.

(a) If a teacher has 10 years of experience, what is the forecasted salary?

Here we have X = 10

Y = 23,313.22 + 1,210.89(10)

Y = 23,313.22 + 12,108.9

Y = 35,422.12

(b) If a teacher has 5 years of experience, what is the forecasted salary?

Here we have X = 5

Y = 23,313.22 + 1,210.89(5)

Y = 23,313.22 + 6,054.45

Y = 29,367.67

(c) Based on this equation, for every additional year of service, a teacher could expect his or her salary to increase by how much?

For every additional year of service, a teacher could expect an increase of 1,210.89.

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2 years ago

Find the area of the shape shown below.

erastova [34]

Answer:10 is the area

Step-by-step explanation:

6 0

3 years ago

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