Which of the following ordered pairs is a solution to the inequality y>−2x+7?

Juliette [100K]

First add 7d to both sides:
-22 = 11d
Now divide by 11 both sides
-2 = d

You can work on either side of the equation, I used the right side for the variables because it was easier to add to positive numbers than dealing with negative numbers on the left side:
-7d -4d = 22
-11d =22
d = -2

either way you get the same answer :)

4 0

3 years ago

Can someone tell me step by step how to solve this?

sasho [114]

Answer:

Step-by-step explanation:

I take it that this is some sort of ratio. Start by solving the brackets on the left.

Brackets: 1/3 - 1/10

Brackets: 10/30 - 3/30

Brackets: 7/30

Brackets^2: 49/900

Brackets^2 - 1/5: 49/900 - 180/900

Brackets^2 - 1/5: -131/900

(2/5)^2 = 4/25

The way this read, it should be

$\frac{\frac{-131}{900} }{\frac{4}{25} }$

Which when you invert and multiply becomes

$\frac{-131}{900} * \frac{25}{4}$

which finally becomes

$\frac{-131}{144}$

7 0

3 years ago

Esther drove to work in the morning at an average speed of 45 miles per hour. She returned home in the evening along the same ro

nydimaria [60]

The key is Esther travelled the same distance - x - in both her morning and evening commute.

45(time she took in the morning, or p) = x
30(time she took in the evening, or q) = x

Therefore 45(p) = 30(q), or divide both sides by 5 and get 9(p) = 6(q). I know you can divide it further, but these numbers are small enough and it's not worth the time.

Since the whole trip took an hour, (p + q) = 60min, and so, p = 60-q.

Therefore 9(60-q) = 6q or 540-9q = 6q. So 540 = 15q, which makes q = 36. If q = 36, then by (p+q)=60, p (the time she took in the morning) must equal 24.

45 miles per hour, her speed in the morning, times (24/60) hours, her time, makes 18 miles travelled in the morning. If you check, 30 miles per hour times (36/60) hours also makes 18 miles in the evening.

<span>Hope that makes a little sense. And I also hope it's right</span>

7 0

3 years ago

Read 2 more answers

A, B & C lie on a straight line.

Liono4ka [1.6K]

Answer:

x = 129°

Step-by-step explanation:

∠ ABD and ∠ DBC are a linear pair and sum to 180° , then

y + ∠ DBC = 180°

107° + ∠ DBC = 180° ( subtract 107° from both sides )

∠ DBC = 73°

the exterior angle of a triangle is equal to the sum of the 2 opposite interior angles , then

x = ∠ DBC + z = 73° + 56° = 129°

8 0

2 years ago

Dos motos, A y B, toman la salida en una carrera de 90 km. La moto A realiza el recorrido con una velocidad media inferior en 20

aleksandr82 [10.1K]

Answer:

motorcycle A: 180 km/h

motorcycle B: 200 km/h

Step-by-step explanation:

To solve this question we need to write a system of equations for A and B, using the equation:

distance = speed * time

The speed of A is 20 less than the speed of B, so:

speedA = speedB - 20

And the time A traveled is 3 minutes (0.05 hours) more than B's time, so:

timeA = timeB + 0.05

Then, using the distance equation, we have that:

distanceB = speedB * timeB

90 = speedB * timeB

distanceA = speedA * timeA

90 = (speedB - 20) * (timeB + 0.05)

90 = speedB * timeB + 0.05 * speedB - 20*timeB - 1

90 = 90 + 0.05 * speedB - 20*timeB - 1

20*timeB = 0.05 * speedB - 1

timeB = (speedB - 20)/400

using this timeB in the distance equation, we have:

90 = speedB * (speedB - 20)/400

90 * 400 = speedB^2 - 20*speedB

speedB^2 - 20*speedB - 36000 = 0

Solving this quadratic equation, we have speedB = 200 km/h

And the speedA is:

speedA = speedB - 20 = 200 - 20 = 180 km/h

6 0

3 years ago