If 18 g of air has 48 J of heat added to it, what will be the change temperature? (C = 0.25 J/g x°C)

Elimination_4x_2y=14 _10x+7y=_24

Gnesinka [82]

Answer:

The answer is $x=-\frac{50}{8}$ and $y=\frac{11}{2}.$

Step-by-step explanation:

Given:

-4x-2y=14

-10x+7y=-24

Now, to solve it by elimination:

$-4x-2y=14$ ......(1)

$-10x+7y=-24$ ......(2)

So, we multiply the equation (1) by 7 we get:

$-28x-14y=98$

And, we multiply the equation (2) by 2 we get:

$-20x+14y=-48$

Now, adding both the new equations:

$-28x-14y+(-20x+14y)=98+(-48)$

$-28x-14y-20x+14y=98-48$

$-28x-20x-14y+14y=50$

$-8x=50$

Dividing both the sides by -8 we get:

$x=-\frac{50}{8}$

Now, putting the value of $x$ in equation (1):

$-4x-2y=14$

$-4(-\frac{50}{8})-2y=14$

$\frac{200}{8} -2y=14$

$25-2y=14$

Subtracting both sides by 25 we get:

$-2y=-11$

Dividing both sides by -2 we get:

$y=\frac{11}{2}$

Therefore, the answer is $x=-\frac{50}{8}$ and $y=\frac{11}{2}.$

5 0

3 years ago

Help me solve thank you will give 20 points

laila [671]

Answer:

Natalie bought 500 apples at $0.40 each, then she pays $0.40 500 times, this means that the total cost of the 500 apples is:

Cost = 500*$0.40 = $200

Now she threw away n apples from the 500 apples, then the number of apples that she has now is:

apples = 500 - n

And she sells the remaining apples for $0.70 each.

a) The amount that she gets by selling the apples is:

Revenue = (500 - n)*$0.70

b) We know that she did not make a loss, then the revenue must be larger than the cost, this means that:

cost ≤ revenue

$200 ≤ (500 - n)*$0.70

c) We need to solve the inequality for n.

$200 ≤ (500 - n)*$0.70

$200/$0.70 ≤ (500 - n)

285.7 ≤ 500 - n

n + 285.7 ≤ 500

n ≤ 500 - 285.7

n ≤ 214.3

Then the maximum value of n must be equal or smaller than 214.3

And n is a whole number, then we can conclude that the maximum number of rotten apples can be 214.

8 0

3 years ago

PLZ I NEED HELP THIS IS PART OF A TEST

shepuryov [24]

Answer:

6.25 inches

Step-by-step explanation:

25/4=6.25

4 0

3 years ago

Read 2 more answers

One of our brainliest, Konrad509, made this:

Reil [10]

$\dfrac{B_x \sqrt{74_x}}{1D_x}+J_x51_x=4G3_x$

A=10, B=11, C=12, etc.

$\dfrac{11\cdot x^0\cdot \sqrt{7\cdot x^1+4\cdot x^0}}{1\cdot x^1+13\cdot x^0}+19\cdot x^0\cdot (5\cdot x^1+1\cdot x^0)=4\cdot x^2+16\cdot x^1+3\cdot x^0\\\\\dfrac{11\sqrt{7x+4}}{x+13}+19(5x+1)=4x^2+16x+3\\\\\dfrac{11\sqrt{7x+4}}{x+13}+95x+19=4x^2+16x+3\\\\11\sqrt{7x+4}+95x(x+13)+19(x+13)=(4x^2+16x+3)(x+13)\\\\11\sqrt{7x+4}+95x^2+1235x+19x+247=4x^3+52x^2+16x^2+208x+3x+39\\\\11\sqrt{7x+4}=4x^3-27x^2-1043x-208\\\\121(7x+4)=(4x^3-27x^2-1043x-208)^2$

$121(7x+4)=(4x^3-27x^2-1043x-208)^2\\\\847x+484=16 x^6 - 216 x^5 - 7615 x^4 + 54658 x^3 + 1099081 x^2 + 433888 x + 43264\\\\16 x^6 - 216 x^5 - 7615 x^4 + 54658 x^3 + 1099081 x^2 + 433041 x +42780=0$

Now, the "only" thing that remains to do is solving the above equation.

While making this problem I only made sure it has a solution. I didn't try to solve it myself and I didn't know it will end up with such "convoluted" polynomial. Sorry to everyone who tried to solve it... m(_ _)m

I think the best way to approach it is using the rational root theorem since we know that $x\in\mathbb{N}$ . Moreover we can deduce that $x\geq19$ since there is $J$ and $J=19$ .