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2 years ago

Evaluate: x(y – 5) for x = 2 and y = 7

Mathematics

1 answer:

KATRIN_1 [288]2 years ago

4 0

Answer:

Step-by-step explanation:

2(7-5)=4

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Miguel biked 14 km in the same amount of time that linda hiked 10 km. Miguel's rate was 4 km/h more than linda's. How fast did e

matrenka [14]

The first thing we must do is define a variable.

We have then:

x: Linda's speed.

Then, by definition, the time traveled is equal to the distance between the velocity.

We have then:

For Linda:

$t = \frac{10}{x}$

For Miguel:

$t = \frac{14}{x + 4}$

Then, since time is the same, then:

$\frac{10}{x} = \frac{14}{x + 4}$

Clearing Linda's speed we have:

$10 (x + 4) = 14x$

$10x + 40 = 14x$

$40 = 14x-10x$

$40 = 4x$

$x = \frac{40}{4}$

$x = 10$

Then, Miguel's speed is:

$x + 4 = 10 + 4 = 14$

Answer:

Linda's speed is 10 Km/h

Miguel's speed is 14 Km/h

3 0

3 years ago

There were 7 pizzas. 5 people ate all of the pizzas. each person ate an equal amount of pizza. how much pizza did each person ea

shtirl [24]

Answer: D

Step-by-step explanation:

A seems complicated and doesn’t make an sense while D is simple

3 0

3 years ago

Which pair of terms are like terms?

sdas [7]

Answer:

b: -2y and 4y

Step-by-step explanation:

The answer is option B

-2y and 4y are like terms because they have the same algebraic alphabet at the back of their coefficients.

6 0

3 years ago

Solve the system by adding. Drag and drop numbers into the coordinates to complete the ordered pair.

Mademuasel [1]

Answer:

(-3,5)

Step-by-step explanation:

4x + 3y = 3

x − 3y = −18

Solve by addition/Elimination

x = -3

y = 5

So,

The solution of the system is (-3,5).

HELPPP PLZZ (I got you)

8 0

2 years ago

Read 2 more answers

If 150 grams of a radioactive isotope are present at 2:00 PM and 10 grams remain at 6:00 PM (the same day), what is the half-lif

pogonyaev

Initial amount, $A_o=150\ g$ .

Final amount, $A =10\ g$ .

Time taken, t = 6:00 - 2:00 = 4 hour.

We know,

$A=A_o(\dfrac{1}{2})^{\dfrac{t}{h}}\\\\10 = 150 \times \dfrac{1}{2}^{\dfrac{4}{h}}\\\\2^{\dfrac{4}{h}}=15\\\\\dfrac{4}{h}= log_215\\\\h = \dfrac{4}{log_215}\\\\h = 1.024 \ hours$

Therefore, the half-life of the isotope is 1.024 hours.

Hence, this is the required solution.

8 0

3 years ago