Solve each pair of simultaneous equation only by substitution method
8x+3y=7
3x+5y= -9

Answers

Answer 1
Answer: x = 2, y = -3

8x + 3y = 7
3y = -8x + 7
y = -8/3x + 7/3

3x + 5y = -9
3x + 5(-8/3x + 7/3) = -9
3x - 40/3x + 35/3 = -9
9/3x - 40/3x + 35/3 = -27/3
-31/3x = -62/3
-31x = -62
x = 2

8(2) + 3y = 7
16 + 3y = 7
3y = -9
y = -3

Check
3(2) + 5(-3) = -9
6 - 15 = -9
-9 = -9 :)

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write as an equation and solve: when 4 is added to the number that is produced by three times the number p, the result is equal to 25.
Can someone explain the answer llease? I dont understand.
What number is 22% of 320?         A. 7040   B. 70.4   C. 704   D. 7.04

Plzz I need help
math word problem

Answers

Answer:

there is 600 seats in the room

Step-by-step explanation:

formula you do 12x 40 then  3x40

A jewelry maker will use 24 blue beads and 30 green beads to make necklaces. What are the possible number of necklaces she can make if each necklace has the same number of blue and green beads? How many of each type will be on each necklace?

Answers

Answer:

  • 1 necklace: 24 blue, 30 green
  • 2 necklaces: 12 blue, 15 green (each)
  • 3 necklaces: 8 blue, 10 green (each)
  • 6 necklaces: 4 blue, 5 green (each)

Step-by-step explanation:

The greatest common factor of 24 and 30 is 6. The divisors of 6 are 1, 2, 3, and 6. Those are the numbers of identical necklaces that might be made from the beads. The number of beads of each color is found by dividing the total number of beads by the number of necklaces being made.

The possible numbers of necklaces are 1, 2, 3 or 6.

The numbers of (blue, green) beads on each will be (24, 30), (12, 15), (8, 10), or (4, 5), respectively.

_____

The greatest common factor (GCF) is the product of the common prime factors.

  24 = 2^3×3

  30 = 2×3×5

The prime factors in common are 2 and 3, so the GCF is 2×3 = 6.

58 is 16% of what number

Answers

16% -------- 58

100% ........ x

Cross multiply

100*58 = 16x

5800 = 16x

x= 5800/16

x = 363

I hope that's help !

A lake in East Texas was stocked with 3,000 trout in the year 2000. The number of fish in the lake is modeled by f(x) = 3000 + 100x, where x represents the number of years after 2000 until 2016. Which of the following is the most reasonable domain for the function?

Answers

The domain of a function is the set of input values the function can take.

The reasonable domain of the function is [0,16]

From the question, we understand that x represents the number of years after 2000 until 2016.

  • In 2000, the value of x is 0
  • In 2016, the value of x is 16

Hence, the reasonable domain of the function is [0,16]

Read more about domain at:

brainly.com/question/10197594

Answer:

x_>0,_>3000

Step-by-step explanation:

I saw the answer key :)

Rennin is an enzyme that digests:A : Bread

B : milk

C : Potatoes

D : Lettuce

Answers

Rennin is an enzyme that digests (b) milk. Rennin is also known as chymosin. This is enzyme digests protein.

Can you plz help me on this?

Answers

Answer:

B 2x-31 = -2x-31

Step-by-step explanation:

A is exactly the same on the left side as the right so it has infinite solutions

B 2x-31 = -2x-31

 Add 2x on each side

2x+2x-31 = -2x+2x-31

4x -31 = 31

Add 31

4x =62

This has one solution

C 2x+31 = 2x-31

Subtract 2x from each side

31 = -31

This is never true so it has no solutions

D 2x-2 = 2x-31

Subtract 2x from each side

-2 = -31

This is never true so it has no solutions

Answer:

B)

Step-by-step explanation:

2x - 31 = -2x - 31

4x = 0

x = 0

x = 0 is the only solution