1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
creativ13 [48]
3 years ago
6

John is twice as old as Mary. The sum of their ages is 21. How old is Mary? Let J = John's age and M = Mary's age. Select the sy

stem equations that represents the problem.
J - 2M = 0
M - 2J = 0
J + M = 21
J = M + 2
Mathematics
2 answers:
AnnZ [28]3 years ago
4 0
ANSWER

The system of equations are,

J - 2M = 0
and

J + M = 21

EXPLANATION

Let J = John's age and M = Mary's age

The first statement says,

"John is twice as old as Mary."

We can write this mathematically as,

J = 2M

or

J - 2M = 0...eqn1

The second statement says,

"the sum of their ages is 21." Mathematically, we can write this one too as,

J + M = 21...eqn2
Ahat [919]3 years ago
3 0
J = 2m
J + M = 21
J + M = 21 is your answer.
You might be interested in
I sent a picture down below​
musickatia [10]

Answer:

A)

Step-by-step explanation:

The letter of the corners go in the same order for both triangles

3 0
3 years ago
Read 2 more answers
This list shows the amount needed to make 8 pancakes 240g plain flour 2 eggs 600ml milk Dan wants to make 12 pancakes. How much
tia_tia [17]

Hi!

We know the amount needed to make 8 pancakes. Dan wants to make 12 pancakes. 12/8 = 1,5, that's the ratio, we need to multiply each ingredient with 1.5 and we will get the amount needed to make 12 pancakes.

240 * 1,5 = 360 g of plain flour

2 * 1,5 = 3 eggs

600 * 1,5 = 900 ml of milk

Hope this helps!

8 0
3 years ago
If a parallelogram is a rhombus the diagonals are, similar, Collinear, congruent, or perpendicular
Elena L [17]
Okay the question is simple provided you understand what these 4 terms mean. I imagine that must be the sticking point here.

In the geometric sense, similarity means one thing scales to another. This doesn't make a huge amount of sense with regards to a single length. But if you have a triangle of lengths 3,4,5 and another of lengths 6,8,10, these are similar because it is all in the same proportion. The only difference is one is twice as large in the length sense.

Collinear means on the same line. Again this doesn't make a huge amount of sense in this context, usually we refer to points being collinear, for example (1,1), (2,2) and (3,3) are all on the same line y = x. In this context, it is saying that both diagonals are exactly the same line, which doesn't make sense.

Congruence, in the geometric sense, means the same. A 3,4,5 triangle can only be congruent to another 3,4,5 triangle. This then is saying that the lengths of the two diagonals are the same in a rhombus. This is indeed true, a property that can be proved using elementary vector geometry.

Finally we have perpendicularity, the property in two dimensions whereby two lines have an angle of 90 degrees between them. In fact only a very special rhombus will have this property, a square. Hence this isn't likely to be the answer to the question because it is not true for all rhombi.

The answer is congruent. I hope this helps :)
8 0
4 years ago
(3 A sum of money doubles itself in 6 years. In how many years, it becomes 5 times? ​
elena-s [515]

Answer:

In 24 years.

Step-by-step explanation:

Let the sum of money be 100 which amounts to 200 ( doubles itself ) in 6 years time. Interest on 100rs. Is 100. Putting the following in simple interest formula. You get :

100=\dfrac{100\times R\times 6}{100}\\\\R=\dfrac{100}{6}

Now when 100 will become 5 times i.e 500 the interest will be 400rs.

Putting in simple interest formula:

400=\dfrac{\dfrac{100\times 100}{6T}}{100}\\\\T=\dfrac{2400}{100}\\\\=24\ yrs

So, in 24 years, it will become 5 times.

4 0
3 years ago
12)
Jlenok [28]

Answer:

Ato find the vertex

Step-by-step explanation:

6 0
3 years ago
Other questions:
  • Name a pair of corresponding sides
    14·1 answer
  • Draw a model write an equation and solve
    11·1 answer
  • Rahim is constructing a proof to show that the opposite angle of a quadrilateral in a circle are supplementary what step would b
    15·2 answers
  • Find both points on the line y = 3 that are 10 units from (3, -3).
    13·1 answer
  • Which equation represents a quadratic function?
    11·2 answers
  • Find the final amount for a $300 investment at $5 interest compounded continuously for 4 years.​
    6·1 answer
  • Can I get the steps of solving the fractions ?
    6·1 answer
  • On a coordinate plane, a curved line labeled f of x with a minimum value of (1.9, negative 5.7) and a maximum value of (0, 2), c
    15·1 answer
  • I will mark brainliest please help ​
    12·1 answer
  • A farmer grows watermelons and cantaloupes. Let X represent the weight of the watermelon, and let Y represent the weight of a ca
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!