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2 years ago

What is the value of the expression 2x2+3xy-y2, when x=2 And y=-4

1 answer:

7 0

Plug in 2 for x, and -4 for y

2(2)² + 3(2)(-4) - (-4)²

2² = 4(2) = 8
3(2) = 6(-4) = -24
-4² = 16

8 - 24 - 16 = answer

Simplify.

answer = 8 - 40
answer = -32

-32 is your answer

hope this helps

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The equation A=1250(1.03)^7 is being used to calculate the amount of money in a savings account. What does the 1.03 represent in

Lelechka [254]

Answer:

The amount of Interest

Step-by-step explanation:

I'm 98% sure. It make sense because that how much interest ^7 you would multiply by 1250. And I've had questions like this. Hope this helps!

8 0

2 years ago

In the air, it had an average speed of 16 m/s In the water, it had an average speed of 3 m/s before hitting the seabed. The tota

julia-pushkina [17]

<h2>The stone fall in air for 7 seconds and fall in water for 5 seconds.</h2>

Step-by-step explanation:

Total distance to sea bed = 127 m

Let the distance traveled in air be s.

Distance traveled in water = 127 - s

Average velocity in air = 16 m/s

Average velocity in water = 3 m/s

Distance traveled in air = Average velocity in air x Time in air

s = 16 x t₁

$t_1=\frac{s}{16}$

Distance traveled in water = Average velocity in water x Time in water

127-s = 3 x t₂

$t_2=\frac{127-s}{3}$

We have total time is 12 seconds

That is

t₁ + t₂ = 12

$\frac{s}{16}+\frac{127-s}{3}=12\\\\3s+2032-16s=576\\\\13s=1456\\\\s=112m$

We have

s = 16 x t₁

112 = 16 x t₁

t₁ = 7 s

t₁ + t₂ = 12

7 + t₂ = 12

t₂ = 5 s

The stone fall in air for 7 seconds and fall in water for 5 seconds.

7 0

2 years ago

Ed eats 6 pieces of fruit. He can eat strawberries or grapes. Show the ways Ed could pick which fruit to eat.

vodka [1.7K]

g=grapes

s=strawberries

0g+6s

1g+5s

2g+4s

3g+3s

4g+2s

5g+1s

6g+0s

8 0

2 years ago

Evaluate - 2y + x(-3)<br> When x = -5 y = 3

Viktor [21]

Answer:

Step-by-step explanation:

2(6) + -5(-3)

= 12+15

= 27

4 0

2 years ago

Read 2 more answers

The Calm Spa charges annual fee of $125 plus $10 per hour of use. The Relax Spa charges annual dues of $230 plus $7 per hour of

Oksi-84 [34.3K]

Answer:

The total number of hours = 35 hours.

Step-by-step explanation:

The annual fee of Calm Spa = $125

Per hour charge of Calm Spa = $10

Annual fee of Relax Spa = $230

Per hour charge of Relax Spa = $7

Now we have to find the number of hours for which both have same cost.

Let the number of hours = x

Thus, 125 + 10x = 230 + 7x

10x-7x = 230 – 125

3x = 105

x = 35

The total number of hours = 35 hours.

6 0

2 years ago