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3 years ago

Five times a certain number, minus 5, is equal to 7 more than three times the number. What is the number

Mathematics

1 answer:

JulijaS [17]3 years ago

4 0

Answer:

Step-by-step explanation:

let’s start with putting the unknown to x, in this case it is the number.

5x-5=7+3x, so now we just solve this equation.

5x-3x=7+5

2x=12

x=6

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Which of the algebraic expressions are not linear expressions? Select all that apply. a. 3x - 2 b. -9y c. -7x^2^ + 4x d. -1/2x^2

Sedaia [141]

Answer:

c, d and e

Step-by-step explanation:

A linear expression is an expression in which sum of exponents of variables is at most 1 in each of its terms.

Option a: $3x - 2$

Here, the exponent of the variable is 1.

So, it is a linear expression.

Option b: $-9y$

Here, the exponent of the variable is 1.

So, it is a linear expression.

Option c: $-7x^2 + 4x$

Here, the highest exponent of the variable is 2.

So, it is NOT a linear expression.

Option d: $-\frac{1}{2} x^2$

Here, the exponent of the variable is 2.

So, it is NOT a linear expression.

Option e: $8xy$

Here, sum of exponents of variables is 2.

So, it is NOT a linear expression.

Hence, c, d and e are NOT algebraic expressions.

6 0

3 years ago

A phone call starts at 9:14a.m. the call lasts for 24 minutes. what time does the call end?

madam [21]

Answer:

It would end at 9:38

Step-by-step explanation:

but obviously it is not one of the answer choices, so I would go with 9:42

3 0

3 years ago

Read 2 more answers

The sum of a number and five divided by fifteen

natta225 [31]

Answer:

Option F

Step-by-step explanation:

Let the number be n.

Sum of a number and 5 is n + 5.

Sum of a number and five divided by fifteen is

( n + 5 ) / 15

5 0

2 years ago

What is the value of this expression? 7d squared+10 d=3

elixir [45]

The answer is 451
- hope this helped-

4 0

3 years ago

Read 2 more answers

at maximum speed, an airplane travels 1720 miles against th wind in 5 hours. Flying with the wind, the plane can travel the same

iragen [17]

Answer:

x = 387

Step-by-step explanation:

The wind acts in the opposite direction to the plane when the time is longer.

The wind acts in the same direction as the plane when the time is shorter.

Equation

d = r*t

Givens

d = 1720
x = plane's speed
y = wind speed
t1 = 5 hours
t2 = 4 hours.

Substitution

d = (x + y) * t
1720 = (x + y) * 4
1720 = (x - y) * 5

Since the two distances are the same, you can equate the right hand sides.

(x + y) * 4 = (x - y)*5 Remove the brackets.
4x + 4y = 5x - 5y Add 5y to both sides
4x + 4y + 5y = 5x - 5y + 5y Combine all the terms.
4x + 9y = 5x Subtract 4x from both sides
9y + 4x - 4x = 5x - 4x Combine
9y = x

Now use one of the given equations with the distance

1720 = (x + y)*4 Substitute 9y for x
1720 = (9y + y) * 4 Combine
1720 = 10y * 4 Multiply the right
1720 = 40y Divide by 40
1720/40 = 40y/40 Do the division
43 = y y = wind speek
9y = x x = 9*y
9*43 = x
x = 387 miles per hour.

4 0

3 years ago